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Question
Find GM of two positive numbers whose A.M. and H.M. are 75 and 48
Solution
A.M. = 75, H.M. = 48
∵ (G.M.)2 = (A.M.) (H.M.)
∴ (G.M.)2 = 75 × 48
= 25 × 3 × 16 × 3
= 52 × 42 × 32
∴ G.M. = 5 × 4 × 3
∴ G.M. = 60
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