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प्रश्न
If `4/5` , a, 2 are three consecutive terms of an A.P., then find the value of a.
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उत्तर
Here, we are given three consecutive terms of an A.P.
First term (a1) = `4/5`
Second term (a2) = a
Third term (a3) = 2
We need to find the value of a. So, in an A.P. the difference of two adjacent terms is always constant. So, we get,
d = a2 - a1
d = a - `4/5` ................(1)
Also,
d = a3 - a2
d = 2 -a ...................(2)
Now, on equating (1) and (2), we get,
`a - 4/5 = 2 - a`
` a + a = 2 +4/5`
`2a = (10 + 4)/5`
`a = 14/10`
`a = 7/5`
Therefore, `a = 7/5`
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