Tommy walks from his home at (0,0) 
i.e Home is at H ( 0,0)
To the mall 
Mall is at M (0, 6)
walks to a movie theater at 
Theater , T( 5, 6)
 Tommy walks to the store at 
Store is at S (5,0) 
Plot each coorinates on the graph :
each grid of square represent one block :
i.e. number of blcok from H to M = 5
Then number of bocks frm M to T is 6 blocks
Number of blocks fromT to S is 5 blocks
Number of blocks from S to H is 6
So total number if blocks are = 5 + 6 + 5 + 6
Number of blocks Tommy walks = 22 blocks
Answer : 22 blocks