Question

Find the mean proportional of the following:

₹ 5, ₹ 125

Answer 1

Let x be the mean proportional between ₹ 5 and ₹ 125

Then,

5 : x :: x : 125

⇒ 5 : x = x : 125

⇒ `5/x = x/125`

⇒ x × x = 5 × 125

⇒ x² = 625

⇒ x = `sqrt625`

⇒ x = ₹ 25