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Question
If 18, a, (b - 3) are in AP, then find the value of (2a – b)
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Solution
It is given that 18, a,(b-3) are in AP.
∴ a-18 = (b-3) -a
⇒ a+a-b = 18-3
⇒ 2a -b = 15
Hence, the required value is 15.
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