Question

WILL DO BRAINIEST!!!The cost of paper varies directly with the number of reams bought. Suppose 2 reams cost $5.10.

Answer 1

Divide $5.10 by 2 which will get you $2.55

Times $2.55 by 15 which will get you $38.25

OR

Divide 15 by 2 which will get you 7.5

Times $5.10 by 7.5 which will get you $38.25

Answer 2

7.5 times as many reams will cost 7.5 times as much money.

7.5*$5.10 = $38.25

The cost of 15 reams of paper is $38.25.

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You know, of course, that 15 = 7.5 * 2.