Question

before getting to school john has a few errands to run john has to walk 5 blocks to the galley and 9 blocks to the library before walking the final 7 blocks to arrive at school if john has already walked 12 blocks how many more blocks must he walked before arriving school

Answer 1

9 blocks

Explanation:

The total of what John has already walked and the number more he must walk will be equal to the number he has to walk to get to school.

12 + more = 5 + 9 + 7

more = 9 + 5 + 7 - 12 . . . . . subtract 12 from both sides

more = 9

John must walk 9 blocks more.

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We recognize that 5+7 = 12, so that last part of the sum totals zero.