Elliot's sister is 17 years old, and her age is 7 years more than half of Elliot's age (! GIVEN !)
Hence, half of Elliot's age is 17 - 7 = 10 years; then Elliot's total age is 20 years. ANSWER
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Elliot's sister's age is 7 years more than half his age. She is now 17 years old. How old is Elliot ?
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SEVENTEEN is 7 years more than half ELLIOT'S age. ... How old is Elliot ?
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