Question 1156608
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When Bob was 12, his sister was half his age, which is 6.<br>
When Bob was 12, his grandmother was 5 times his age, minus half his sister's age: 5(12)-(1/2)6 = 60-3 = 57.<br>
His grandmother is now 60, so Bill was 12 3 years ago.<br>
ANSWER: Bob is now 15.<br>