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Question
If the numbers a, 9, b, 25 from an AP, find a and b.
Solution
It is given that the numbers a,9,b,25from an AP.
∴ 9- a = b-9 = 25-b
So,
b-9=25-b
⇒ 2b = 34
⇒ b = 17
Also,
9 - a = b - 9
⇒ a= 18 -b
⇒ a = 18 - 17 (b=17)
⇒ a =1
Hence, the required values of a and b are 1 and 17, respectively.
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