← Reasoning

Grade 6-1

45 problems

Compute with newly defined operations
Fraction and Decimal Calculations
Simplify complex fractions
Fraction and Decimal Calculations
Simplify messy fraction-decimal expressions
Fraction and Decimal Calculations
Batting average and win rate
Ratio and Rate (2)
Work rates add, times do not
Ratio and Rate (2)
Newton's cows: grass grows while eaten
Ratio and Rate (2)
Volume of a composite solid
Volume of Solid Figures
Volume of prisms and pyramids
Volume of Solid Figures
Water height from base area
Volume of Solid Figures
Counting painted unit cubes
Surface Area and Volume of Solids
Largest and smallest surface area
Surface Area and Volume of Solids
Surface area of a composite solid
Surface Area and Volume of Solids
Complete a syllogism from two premises
Deductive Logic (1)
Deduction table decides a one-to-one matching
Deductive Logic (1)
Fewest groups with no conflicting pair
Deductive Logic (1)
Case-split on a hypothetical condition
Deductive Logic (2)
Fewest river crossings under rules
Deductive Logic (2)
Seat people from adjacency clues
Deductive Logic (2)
Recover an answer key from scores
Truth and Falsehood
Exactly one statement is true
Truth and Falsehood
Truth-tellers and liars
Truth and Falsehood
Angle between the hands at a given time
Clocks and Angles
When the hour and minute hands overlap
Clocks and Angles
Read the time on a numberless clock
Clocks and Angles
Complete a partial net of a prism or pyramid
Prisms and Pyramids
Count vertices, faces, edges of prisms and pyramids
Prisms and Pyramids
Euler's formula for polyhedra
Prisms and Pyramids
Edges of a solid from its net
Using Nets
Different ways to finish a net
Using Nets
Shortest string tied around a box
Using Nets
Faces, edges, vertices and Euler's formula
Regular Polyhedra
Vertex labels on a regular octahedron net
Regular Polyhedra
Defining regular polyhedra and why only five
Regular Polyhedra
Dual polyhedron from face centers
Dual and Semiregular Polyhedra
Semiregular solids by cutting off vertices
Dual and Semiregular Polyhedra
Descartes' angle-defect theorem
Dual and Semiregular Polyhedra
Catching up: subtract the two speeds
Distance and Speed (1)
Compare speeds by a common unit rate
Distance and Speed (1)
Meeting head-on: add the two speeds
Distance and Speed (1)
Boat speed with and against a current
Distance and Speed (2)
Round trip at two different speeds
Distance and Speed (2)
Train passing completely through a tunnel
Distance and Speed (2)
Percent change in a price
Ratio and Rate (1)
Recover the whole from a percent
Ratio and Rate (1)
Concentration of a salt solution
Ratio and Rate (1)