Answer is 3
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Work Shown:
The mixed number 1 & 1/2 converts to
1 & 1/2 = 1 + 1/2 = 1 + 0.5 = 1.5
Then we multiply it with 2 getting
(1 & 1/2) times 2 = 1.5 times 2 = 3
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Another way you could do it
1 & 1/2 = 1 + 1/2 = 2/2 + 1/2 = 3/2
(1 & 1/2) times 2 = (3/2) times 2 = (3/2) * (2/1) = 6/2 = 3