Answer :
$600
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Add up the fractions John spent:
- 1/2 + 1/3 = 5/6
This means he spent 5/6 of his money, so he has:
- 1 - 5/6 = 1/6 left
If he has $100 left, his original amount can be calculated by dividing $100 by 1/6:
- $100 ÷ 1/6 =
- $100 × 6 =
- $600