18 15 = h 5 ∣ cross m u lt i pl y 15 h = 5 × 18 15 h = 90 ∣ d i v i d e b o t h s i d es b y 15 h = 6
By cross-multiplying the equation 18 15 = h 5 , we find that h = 6 . This shows the equivalence of the two ratios. The calculated value for h is confirmed to be correct.
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