Question

sum of first 9 terms of an ap is 279. find its 10th term of d = 8​

Answer 1

Answer:

287.

Step-by-step explanation:

Given,

$a_{9} = 279 \\ \\ a + (9 - 1)(8) = 279 \\ \\ a + 8 \times 8 = 279 \\ \\ a = 279 - 64 \\ \\ \bf a = 215$

10th term of the AP

$a_{10} = a + (n - 1)d \\ \\ a_{10} = 215 + (10 - 1)(8) \\ \\ a_{10} = 215 + 9 \times 8 \\ \\ a_{10} = 215 + 72 \\ \\ \bf a_{10} = 287$