Problem
Row 2 splits 1400 into two equal halves. Since 700 + 700 = 1400 matches the given right cell, the blank left cell is also 700.
Splitting into two equal parts means each part is half, and half of 1400 is 700.
3.NBT.A.2Look For A PatternIn Row 2, the blank left cell must be 700.
Row 2 is the whole 1400 cut into two equal pieces, so the two cells hold the same number and together they rebuild 1400.
The two cells come from splitting the single 1400 bar with no gap and no overlap, so adding them returns the whole 1400.
The two cells are drawn the same width, and same-width pieces match up piece for piece, so they must stand for the same number.
The right cell is given as 700, and since the two cells are equal, the left cell has to be that same value, 700, and two 700s really do add back to 1400.
Seven hundreds plus seven hundreds make fourteen hundreds, and fourteen hundreds is written as 1400, so the two 700s fill the whole exactly.
Row 3 halves each 700 from Row 2. Half of 700 is 350, matching the given cell, so all four cells are 350 and each blank is 350.
Halving again keeps the equal-pieces pattern: 700 becomes 350 and 350.
3.NBT.A.2Look For A PatternThe four equal cells of Row 3 must still cover the whole 1400. Adding the four 350s gives 1400, so the fill is consistent.
The whole bar is unchanged, so the equal pieces in any row always re-add to 1400.
3.OA.A.4Draw A DiagramThis only needs Grade 3 halving sense: each row just splits the number in half, so 1400 → 700 → 350!