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Question
Find the mean proportion of: 5 and 80
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Solution
Let x be the mean proportion of 5 and 80 ,
then 5 : x : : x : 80
x² = 5 x 80
⇒ x = `sqrt(5 xx 80)`
= `sqrt(400)`
= 20
x = 20
Hence mean proportion = 20.
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