Question

Which term of the ap 3 10 17 ...Will be 84 more than its 13th term?

Answer 1

Step-by-step explanation:

1st find 13th term a

$a = 3 \\ \\ d = second \: term \: - 1st \: term \\ \\ d = 10 - 3 = 7 \\ \\ a13 = \: a + (n - 1)d \\ \\ = 3 + (13 - 1)7 \\ \\ = 3 + 12 \times 7 \\ \\ = 3 + 84 = 87 \\ \\ \\ a13 + 84 = 87 + 84 = 171$

now substitute in n formula u LL get the answers u know last value 171 and 1st term 3