# Find the mean proportional of 48 and 12.

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Find the mean proportional of 48 and 12.
1. 54
2. 36
3. 24
4. 4

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Correct Answer - Option 3 : 24

Given:

Two numbers are 48 and 12.

Concept Used:

When a, b, c and d are called in proportion, where a and d are called extremes and b and c are called means.

Product of extremes = Product of means

i.e. ad = bc

and Mean Proportional of a and b is √(a × b)

Calculation:

Let the mean proportion of 48 and 12 be x.

Here, a = 48 and b = 12

So, a ∶ x = x ∶ b

⇒ a/x = x/b

⇒ a × b = x2

⇒ x = √(a × b)

⇒ x = √(48 × 12)

⇒ x = √(576)

⇒ x = 24

∴ The mean proportional of 48 and 12 is 24.