Answer: 25
Step-by-step explanation: Reading through the problem, we have 60% which can be written as the fraction 60/100, "of" means multiply, "what number" which we can call X, "is 15" equals 15.

If we simplify on the left side of the equation, we can reduce 60/100 to 3/5 so we now have as followed.

We can multiply both sides of the equation by 5 to get rid of the fraction and we have 3x = 75.
3x = 75
÷3 ÷3 ← divide both sides by 3
X = 25
Therefore, 60%of 25 is 15.
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