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Find the fourth proportional to 12, 16, 18.

12, 16, 18 का चतुर्थ समानुपाती ज्ञात कीजिए।

This Question Asked In:

SSC, CGL

A. 20
B. 22
C. 24
D. 26

Correct Answer :C - 24

Detailed Solution Video

Video Credit –Nikhil Sharma Maths

Detailed Text Solution

Let the fourth proportional be x.

By definition of fourth proportional:
12 : 16 = 18 : x

So,
12/16 = 18/x

Cross-multiplying:
12x = 16 × 18
12x = 288

x = 288/12
x = 24

Thus, the fourth proportional is 24.

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