Question

Marta made 4 stacks of wooden blocks. The first stack was 4 blocks tall. The second stack was 7 blocks taller than the first. The third stack was 2 blocks shorter than the second stack, and the last stack was 7 blocks taller than the third stack. How many blocks did Marta use in all?

Answer 1

30 blocks.

Explanation:

1st tower: 4 blocks

2nd tower: 11 blocks (4+7)

3rd tower: 9 blocks (11-2)

4th tower: 16 blocks (9+7)

4+11+9+16=30