The answer is: " 16 " .
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Step-by-step explanation:
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Method 1)
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(4/5) *(20/1) = ?
The "5" cancels to a "1" ; and the "20" cancels to a "4" ;
(since "20÷5=4" ; and "5÷5=1") ;
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Rewrite as: (4/1) * (4/1) = 4 * 4 = 16.
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Method 2)
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4/5 * 20/1 = (4*20)/(5*1) = (80/5) = 16 .
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Method 3)
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4/5 * 20 = ? ;
4/5 = 8/10 = 0.8 ;
0.8 * 20 = 16.0 = 16.
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