Question

Quest- The fourth proportional of the numbers 12, 16, 18 is .....?
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Answer 1

Answer:

Let the fourth proportional to 12, 18, 20 be x. Hence, the fourth proportional to 12, 18, 20 is 30.

Answer 2

Answer:

30

Step-by-step explanation:

Let the fourth proportional to 12, 18, 20 be x.

Then, 12 : 18 :: 20 : x

⇒ 12 × x = 20 × 18 (Product of Extremes = Product of means)

⇒ x = (20 × 18)/12

⇒ x = 30

Hence, the fourth proportional to 12, 18, 20 is 30.