Respuesta :
13. C. 6/7 and 60/70, think of percentages. 16. D. 231, because 4/15 times 315 = 84, 315-84 = 231.
6/7 is the same as 60/70 or
6/7 and 6x10
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7x 10
10/10 is one so
6/7 = 6/7
6/7 and 6x10
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7x 10
10/10 is one so
6/7 = 6/7