Question

Find the decimal fraction which when multiplied by itself gives 84.64.

Answer 1

Let the decimal fraction be x.

When a decimal fraction is multiplied by itself, then product = x × x = x²

But product = 84.64   ...[Given]

∴ x² = 84.64

⇒ x = `sqrt(84.64)`

Now, place the bar over the numbers, then square root is given below.

	9.2
9	`bar84. bar64`
	81
182	364
	364
	0

∴ x = `sqrt(84.64)` = 9.2

Hence, the required decimal is 9.2.