Question

Which term of this arithmetic series is zero: 150, 140, 130 ...?

• A. 16
• B. 17
• C. 15
• D. 18

Answer 1

Answer:

A. 16

The first term, a = 150, common difference is d = -10, n-th term is 0. n-th term tn = a + (n-1)d So 0 = 150 + (n - 1) x-10 - 150 = (n-1)x-10 n - 1 = 150/10 = 15 n=15+ 1 = 16