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Question
If ` 4/5 ` , a , 2 are in AP, find the value of a.
Solution
If 45, a and 2 are three consecutive terms of an AP, then we have:
a - 45 = 2 - a
⇒ 2a = 2 +45
⇒ 2a = 145
⇒ a =75
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