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Question
The first three terms of an AP are respectively (3y – 1), (3y + 5) and (5y + 1), find the value of y .
Solution
The terms (3y -1), (3y +5) and (5y +1) are in AP.
∴ (3 y + 5) - (3y-1) = (5y+1) - (3y+5)
⇒ 3y + 5-3y +1 = 5y + 1-3y-5
⇒6 = 2y-4
⇒ 2y = 10
⇒ y = 5
Hence, the value of y is 5.
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