Elga’s age is 40 and Alvin’s age is 54
7 times of 1/2 cup = 7 x 1/2
7 times of 1/2 cup = 7/2
7 times of 1/2 cup = 3 1/2 cups.
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The recipe called for 3 1/2 cups of flour
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Assuming that you’re asking for a fraction of 0.31 where 31 repeats?
31/99