← Ten tenths make one whole · Place-Value Regrouping

Ten tenths make one whole · 10 practice problems

4.NF.C.64.NF.C.5

Generated variants — 10

Freshly produced from the archetype’s parameters — problem, figure, and solution derived together.

Variant 1 easy answer: 2.5 and 1

Write each number described by the conditions below as a decimal.

the number made of twenty-five 0.1s, and the number that is 10 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of twenty-five 0.1s, and (2) the number that is 10 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is twenty-five copies of 0.1
  • The second number is 10 times 0.1
Unknowns
  • The decimal equal to twenty-five 0.1s
  • The decimal equal to 10 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 25 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group twenty-five 0.1s into bundles of ten. 2 bundle(s) of ten tenths give 2 whole(s) (2.0), and 5 tenths are left over, which is 0.5.
25×0.1=20×0.1+5×0.1=2+0.5=2.525 \times 0.1 = 20 \times 0.1 + 5 \times 0.1 = 2 + 0.5 = 2.5
Tenths bundle into wholes exactly the way ones bundle into tens, so 25 tenths is 2 wholes and 5 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
2 whole(s) and 5 tenths is written as 2.5.
25×0.1=2.525 \times 0.1 = 2.5
The digit before the point counts wholes; the digit after counts tenths.

310 times 0.1

#5 Look for a Pattern 4.NF.C.5
10 0.1s is exactly 1, because every ten tenths make 1.
10×0.1=110 \times 0.1 = 1
Each group of ten copies of one tenth fills up exactly one whole, so 10 tenths is the number 1.
Answer: 2.5 and 1
4 · Reviewdoes it hold up?

25 tenths should be near 2 wholes (since 20 tenths = 2), and 2.5 fits. 10 tenths is 1. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 25 tenths is 2.5, and 10 tenths is 1.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 25 tenths as the decimal 2.5
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 2 medium answer: 3.6 and 1

Write each number described by the conditions below as a decimal.

the number made of thirty-six 0.1s, and the number that is 10 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of thirty-six 0.1s, and (2) the number that is 10 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is thirty-six copies of 0.1
  • The second number is 10 times 0.1
Unknowns
  • The decimal equal to thirty-six 0.1s
  • The decimal equal to 10 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 36 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group thirty-six 0.1s into bundles of ten. 3 bundle(s) of ten tenths give 3 whole(s) (3.0), and 6 tenths are left over, which is 0.6.
36×0.1=30×0.1+6×0.1=3+0.6=3.636 \times 0.1 = 30 \times 0.1 + 6 \times 0.1 = 3 + 0.6 = 3.6
Tenths bundle into wholes exactly the way ones bundle into tens, so 36 tenths is 3 wholes and 6 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
3 whole(s) and 6 tenths is written as 3.6.
36×0.1=3.636 \times 0.1 = 3.6
The digit before the point counts wholes; the digit after counts tenths.

310 times 0.1

#5 Look for a Pattern 4.NF.C.5
10 0.1s is exactly 1, because every ten tenths make 1.
10×0.1=110 \times 0.1 = 1
Each group of ten copies of one tenth fills up exactly one whole, so 10 tenths is the number 1.
Answer: 3.6 and 1
4 · Reviewdoes it hold up?

36 tenths should be near 3 wholes (since 30 tenths = 3), and 3.6 fits. 10 tenths is 1. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 36 tenths is 3.6, and 10 tenths is 1.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 36 tenths as the decimal 3.6
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 3 easy answer: 3.5 and 1

Write each number described by the conditions below as a decimal.

the number made of thirty-five 0.1s, and the number that is 10 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of thirty-five 0.1s, and (2) the number that is 10 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is thirty-five copies of 0.1
  • The second number is 10 times 0.1
Unknowns
  • The decimal equal to thirty-five 0.1s
  • The decimal equal to 10 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 35 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group thirty-five 0.1s into bundles of ten. 3 bundle(s) of ten tenths give 3 whole(s) (3.0), and 5 tenths are left over, which is 0.5.
35×0.1=30×0.1+5×0.1=3+0.5=3.535 \times 0.1 = 30 \times 0.1 + 5 \times 0.1 = 3 + 0.5 = 3.5
Tenths bundle into wholes exactly the way ones bundle into tens, so 35 tenths is 3 wholes and 5 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
3 whole(s) and 5 tenths is written as 3.5.
35×0.1=3.535 \times 0.1 = 3.5
The digit before the point counts wholes; the digit after counts tenths.

310 times 0.1

#5 Look for a Pattern 4.NF.C.5
10 0.1s is exactly 1, because every ten tenths make 1.
10×0.1=110 \times 0.1 = 1
Each group of ten copies of one tenth fills up exactly one whole, so 10 tenths is the number 1.
Answer: 3.5 and 1
4 · Reviewdoes it hold up?

35 tenths should be near 3 wholes (since 30 tenths = 3), and 3.5 fits. 10 tenths is 1. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 35 tenths is 3.5, and 10 tenths is 1.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 35 tenths as the decimal 3.5
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 4 easy answer: 1.6 and 1

Write each number described by the conditions below as a decimal.

the number made of sixteen 0.1s, and the number that is 10 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of sixteen 0.1s, and (2) the number that is 10 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is sixteen copies of 0.1
  • The second number is 10 times 0.1
Unknowns
  • The decimal equal to sixteen 0.1s
  • The decimal equal to 10 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 16 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group sixteen 0.1s into bundles of ten. 1 bundle(s) of ten tenths give 1 whole(s) (1.0), and 6 tenths are left over, which is 0.6.
16×0.1=10×0.1+6×0.1=1+0.6=1.616 \times 0.1 = 10 \times 0.1 + 6 \times 0.1 = 1 + 0.6 = 1.6
Tenths bundle into wholes exactly the way ones bundle into tens, so 16 tenths is 1 wholes and 6 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
1 whole(s) and 6 tenths is written as 1.6.
16×0.1=1.616 \times 0.1 = 1.6
The digit before the point counts wholes; the digit after counts tenths.

310 times 0.1

#5 Look for a Pattern 4.NF.C.5
10 0.1s is exactly 1, because every ten tenths make 1.
10×0.1=110 \times 0.1 = 1
Each group of ten copies of one tenth fills up exactly one whole, so 10 tenths is the number 1.
Answer: 1.6 and 1
4 · Reviewdoes it hold up?

16 tenths should be near 1 wholes (since 10 tenths = 1), and 1.6 fits. 10 tenths is 1. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 16 tenths is 1.6, and 10 tenths is 1.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 16 tenths as the decimal 1.6
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 5 medium answer: 4.2 and 2

Write each number described by the conditions below as a decimal.

the number made of forty-two 0.1s, and the number that is 20 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of forty-two 0.1s, and (2) the number that is 20 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is forty-two copies of 0.1
  • The second number is 20 times 0.1
Unknowns
  • The decimal equal to forty-two 0.1s
  • The decimal equal to 20 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 42 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group forty-two 0.1s into bundles of ten. 4 bundle(s) of ten tenths give 4 whole(s) (4.0), and 2 tenths are left over, which is 0.2.
42×0.1=40×0.1+2×0.1=4+0.2=4.242 \times 0.1 = 40 \times 0.1 + 2 \times 0.1 = 4 + 0.2 = 4.2
Tenths bundle into wholes exactly the way ones bundle into tens, so 42 tenths is 4 wholes and 2 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
4 whole(s) and 2 tenths is written as 4.2.
42×0.1=4.242 \times 0.1 = 4.2
The digit before the point counts wholes; the digit after counts tenths.

320 times 0.1

#5 Look for a Pattern 4.NF.C.5
20 0.1s is exactly 2, because every ten tenths make 1.
20×0.1=220 \times 0.1 = 2
Each group of ten copies of one tenth fills up exactly one whole, so 20 tenths is the number 2.
Answer: 4.2 and 2
4 · Reviewdoes it hold up?

42 tenths should be near 4 wholes (since 40 tenths = 4), and 4.2 fits. 20 tenths is 2. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 42 tenths is 4.2, and 20 tenths is 2.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 42 tenths as the decimal 4.2
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 6 medium answer: 1.2 and 2

Write each number described by the conditions below as a decimal.

the number made of twelve 0.1s, and the number that is 20 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of twelve 0.1s, and (2) the number that is 20 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is twelve copies of 0.1
  • The second number is 20 times 0.1
Unknowns
  • The decimal equal to twelve 0.1s
  • The decimal equal to 20 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 12 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group twelve 0.1s into bundles of ten. 1 bundle(s) of ten tenths give 1 whole(s) (1.0), and 2 tenths are left over, which is 0.2.
12×0.1=10×0.1+2×0.1=1+0.2=1.212 \times 0.1 = 10 \times 0.1 + 2 \times 0.1 = 1 + 0.2 = 1.2
Tenths bundle into wholes exactly the way ones bundle into tens, so 12 tenths is 1 wholes and 2 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
1 whole(s) and 2 tenths is written as 1.2.
12×0.1=1.212 \times 0.1 = 1.2
The digit before the point counts wholes; the digit after counts tenths.

320 times 0.1

#5 Look for a Pattern 4.NF.C.5
20 0.1s is exactly 2, because every ten tenths make 1.
20×0.1=220 \times 0.1 = 2
Each group of ten copies of one tenth fills up exactly one whole, so 20 tenths is the number 2.
Answer: 1.2 and 2
4 · Reviewdoes it hold up?

12 tenths should be near 1 wholes (since 10 tenths = 1), and 1.2 fits. 20 tenths is 2. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 12 tenths is 1.2, and 20 tenths is 2.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 12 tenths as the decimal 1.2
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 7 medium answer: 4.8 and 3

Write each number described by the conditions below as a decimal.

the number made of forty-eight 0.1s, and the number that is 30 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of forty-eight 0.1s, and (2) the number that is 30 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is forty-eight copies of 0.1
  • The second number is 30 times 0.1
Unknowns
  • The decimal equal to forty-eight 0.1s
  • The decimal equal to 30 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 48 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group forty-eight 0.1s into bundles of ten. 4 bundle(s) of ten tenths give 4 whole(s) (4.0), and 8 tenths are left over, which is 0.8.
48×0.1=40×0.1+8×0.1=4+0.8=4.848 \times 0.1 = 40 \times 0.1 + 8 \times 0.1 = 4 + 0.8 = 4.8
Tenths bundle into wholes exactly the way ones bundle into tens, so 48 tenths is 4 wholes and 8 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
4 whole(s) and 8 tenths is written as 4.8.
48×0.1=4.848 \times 0.1 = 4.8
The digit before the point counts wholes; the digit after counts tenths.

330 times 0.1

#5 Look for a Pattern 4.NF.C.5
30 0.1s is exactly 3, because every ten tenths make 1.
30×0.1=330 \times 0.1 = 3
Each group of ten copies of one tenth fills up exactly one whole, so 30 tenths is the number 3.
Answer: 4.8 and 3
4 · Reviewdoes it hold up?

48 tenths should be near 4 wholes (since 40 tenths = 4), and 4.8 fits. 30 tenths is 3. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 48 tenths is 4.8, and 30 tenths is 3.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 48 tenths as the decimal 4.8
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 8 hard answer: 2.7 and 4

Write each number described by the conditions below as a decimal.

the number made of twenty-seven 0.1s, and the number that is 40 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of twenty-seven 0.1s, and (2) the number that is 40 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is twenty-seven copies of 0.1
  • The second number is 40 times 0.1
Unknowns
  • The decimal equal to twenty-seven 0.1s
  • The decimal equal to 40 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 27 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group twenty-seven 0.1s into bundles of ten. 2 bundle(s) of ten tenths give 2 whole(s) (2.0), and 7 tenths are left over, which is 0.7.
27×0.1=20×0.1+7×0.1=2+0.7=2.727 \times 0.1 = 20 \times 0.1 + 7 \times 0.1 = 2 + 0.7 = 2.7
Tenths bundle into wholes exactly the way ones bundle into tens, so 27 tenths is 2 wholes and 7 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
2 whole(s) and 7 tenths is written as 2.7.
27×0.1=2.727 \times 0.1 = 2.7
The digit before the point counts wholes; the digit after counts tenths.

340 times 0.1

#5 Look for a Pattern 4.NF.C.5
40 0.1s is exactly 4, because every ten tenths make 1.
40×0.1=440 \times 0.1 = 4
Each group of ten copies of one tenth fills up exactly one whole, so 40 tenths is the number 4.
Answer: 2.7 and 4
4 · Reviewdoes it hold up?

27 tenths should be near 2 wholes (since 20 tenths = 2), and 2.7 fits. 40 tenths is 4. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 27 tenths is 2.7, and 40 tenths is 4.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 27 tenths as the decimal 2.7
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 9 hard answer: 2.4 and 5

Write each number described by the conditions below as a decimal.

the number made of twenty-four 0.1s, and the number that is 50 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of twenty-four 0.1s, and (2) the number that is 50 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is twenty-four copies of 0.1
  • The second number is 50 times 0.1
Unknowns
  • The decimal equal to twenty-four 0.1s
  • The decimal equal to 50 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 24 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group twenty-four 0.1s into bundles of ten. 2 bundle(s) of ten tenths give 2 whole(s) (2.0), and 4 tenths are left over, which is 0.4.
24×0.1=20×0.1+4×0.1=2+0.4=2.424 \times 0.1 = 20 \times 0.1 + 4 \times 0.1 = 2 + 0.4 = 2.4
Tenths bundle into wholes exactly the way ones bundle into tens, so 24 tenths is 2 wholes and 4 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
2 whole(s) and 4 tenths is written as 2.4.
24×0.1=2.424 \times 0.1 = 2.4
The digit before the point counts wholes; the digit after counts tenths.

350 times 0.1

#5 Look for a Pattern 4.NF.C.5
50 0.1s is exactly 5, because every ten tenths make 1.
50×0.1=550 \times 0.1 = 5
Each group of ten copies of one tenth fills up exactly one whole, so 50 tenths is the number 5.
Answer: 2.4 and 5
4 · Reviewdoes it hold up?

24 tenths should be near 2 wholes (since 20 tenths = 2), and 2.4 fits. 50 tenths is 5. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 24 tenths is 2.4, and 50 tenths is 5.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 24 tenths as the decimal 2.4
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!
Variant 10 hard answer: 2.3 and 6

Write each number described by the conditions below as a decimal.

the number made of twenty-three 0.1s, and the number that is 60 times 0.1

Show solution
1 · Understandwhat's really being asked

We must write two decimals: (1) the number made of twenty-three 0.1s, and (2) the number that is 60 times 0.1.

Givens
  • 0.1 is one tenth, the unit in the tenths place
  • The first number is twenty-three copies of 0.1
  • The second number is 60 times 0.1
Unknowns
  • The decimal equal to twenty-three 0.1s
  • The decimal equal to 60 times 0.1
Constraints
  • Each answer is written in decimal notation
  • Ten 0.1s regroup into 1 whole
2 · Planchoose the strategy

#5 Look for a Pattern · also uses: #9 Solve an Easier Related Problem

Counting tenths follows the place-value pattern that every 10 tenths bundle into one whole. Starting from the easy fact that ten 0.1s make 1, we extend the pattern to 23 tenths and confirm the second number directly.

3 · Execute3 carry out the plan

1Ten tenths make one whole

#9 Solve an Easier Related Problem 4.NF.C.6
Group twenty-three 0.1s into bundles of ten. 2 bundle(s) of ten tenths give 2 whole(s) (2.0), and 3 tenths are left over, which is 0.3.
23×0.1=20×0.1+3×0.1=2+0.3=2.323 \times 0.1 = 20 \times 0.1 + 3 \times 0.1 = 2 + 0.3 = 2.3
Tenths bundle into wholes exactly the way ones bundle into tens, so 23 tenths is 2 wholes and 3 tenths.

2Write the first decimal

#5 Look for a Pattern 4.NF.C.6
2 whole(s) and 3 tenths is written as 2.3.
23×0.1=2.323 \times 0.1 = 2.3
The digit before the point counts wholes; the digit after counts tenths.

360 times 0.1

#5 Look for a Pattern 4.NF.C.5
60 0.1s is exactly 6, because every ten tenths make 1.
60×0.1=660 \times 0.1 = 6
Each group of ten copies of one tenth fills up exactly one whole, so 60 tenths is the number 6.
Answer: 2.3 and 6
4 · Reviewdoes it hold up?

23 tenths should be near 2 wholes (since 20 tenths = 2), and 2.3 fits. 60 tenths is 6. Both magnitudes match the meaning of a tenth.

Another way: Use place value directly (tool 15): 0.1 means 1 in the tenths place, so 23 tenths is 2.3, and 60 tenths is 6.

Standardsmin grade 4
  • 4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100 — Writing 23 tenths as the decimal 2.3
  • 4.NF.C.5 Express a fraction with denominator 10 as equivalent with denominator 100 — Recognizing that ten tenths equal one whole
💡Takeaway. Every ten tenths bundle into one whole, so counting 0.1s is just like counting place values you already know!