Answer: 21/2
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Work Shown:
10.5 = 10 + 0.5
10.5 = 10 + (1/2)
10.5 = (20/2) + (1/2)
10.5 = (20+1)/2
10.5 = 21/2
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Alternative Route:
10.5 = 10.5/1
10.5 = 105/10 <--- multiply top and bottom by 10
10.5 = (21*5)/(2*5)
10.5 = 21/2 <---- cancel the common factors
