Answer:There are 13 more blocks he must walk before arriving at school.
Step-by-step explanation:
Since we have given that
Number of blocks he has walk to the gallery = 4
Number of blocks he has walk to the museum = 10
Number of blocks he has walk to arrive at the school = 7
So, Total number of blocks becomes
[tex]4+10+7=11+10=21\ blocks[/tex]
Number of blocks he already walked = 8
so, remaining blocks would be
[tex]21-8=13\ blocks[/tex]
Hence, there are 13 more blocks he must walk before arriving at school.