Respuesta :
tim used 25 blocks.
4 blocks for the first stack
10 blocks for the second [6 blcoks taller]
3 blocks for the third [7 blocks shorter]
8 blocks for the fourth [5 blocks taller]
4+10+3+8 = 25
4 blocks for the first stack
10 blocks for the second [6 blcoks taller]
3 blocks for the third [7 blocks shorter]
8 blocks for the fourth [5 blocks taller]
4+10+3+8 = 25