sum(8) = (8/2)(2a + 7d) = 60
2a + 7d = 15
sum(50) = (50/2)(2a + 49d) = 880
2a + 49d = 35.2
subtract them:
42d = 20.2
d = 202/420 = 101/210
2a + 7(101/210) = 15
2a = 349/30
a = 349/60
term(43) = a + 42d
= 349/60 + 42(101/210
= 1561/60
The sum of 8th term of an A.P is 60 while the sum of 50th term is 880. Find the 43rd term
2 answers
8/2 (2a+7d) = 50
50/2 (2a+49d) = 880
Solve for a and d, and then evaluate
a+42d
50/2 (2a+49d) = 880
Solve for a and d, and then evaluate
a+42d