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Algebra Difficulty 2.2 Junior Find the answer

If x%x \% of 60 is 12, what is 15%15 \% of xx?

A number or a short expression. Spacing and $ signs are ignored.

Solution

Since x%x \% of 60 is 12, then x100⋅60=12\frac{x}{100} \cdot 60=12 or x=12⋅10060=20x=\frac{12 \cdot 100}{60}=20. Therefore, 15%15 \% of xx is 15%15 \% of 20, or 0.15⋅20=30.15 \cdot 20=3.

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