Question

for an A.P the first term is 14and the last term is 212. if sum of all these terms is 1130 find the no. of terms and common diff​

Answer 1

Answer:

No. of terms = 10, Common difference = 22

Step-by-step explanation:

Given ,

a = 14

 l = 212

$S_{n}$ = 1130

From the formula,

$S_{n} = \frac{n}{2} ( a + l )\\1130 = \frac{n}{2} (14 + 212)\\2260 = 14n + 212n\\2260 = 226n\\\\thus, n = 10$

$l = a + (n-1)d\\212 = 14 + 9d\\198 = 9d\\\\thus , d = 22$