Answer: c = 900
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Explanation:
We are dividing c by 15 to get 60. To isolate c, we undo what is happening to the variable. So we multiply both sides by 15
c/15 = 60
15*(c/15) = 15*60 ... multiply both sides by 15
c = 900
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As a check,
c/15 = 60
900/15 = 60 ... replace every copy of c with 900
60 = 60 .... we get a true equation
Since the last equation is true, this confirms the solution c = 900.
