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Question
The 1st, 3rd, and 4th terms of a proportion are 12, 8, and 14 respectively. Find the 2nd term.
Solution
Let the second term be x.
Then. 12 : x :: 8 : 14
We know:
Product of extremes = Product of means
12 × 14 = 8x
⇒ 168 = 8x
⇒ x = `168/8` = 21
Hence, the second term is 21.
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