Respuesta :

Answer:  18/25 ; or, write as:  0.72  .
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Explanation:
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9/20  * 4/5  = (
9*4) / (10*5) = 36/50 ; 
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36/50 = 
(36÷2) / (50÷2) = 18/25 ; or, write as:  0.72  .
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