In an arithmetic progression a1 = 250 , a17=130 . What is a24 ?
A. 100 B. 85.5 C. 77.5 D. 65 E. 50
OA C
A. 100 B. 85.5 C. 77.5 D. 65 E. 50
OA C
nth term of the sequence is given by an = a1 + (n - 1)d, where a1 is the 1st term and d is the common difference.jainrahul1985 wrote:In an arithmetic progression a1 = 250 , a17=130 . What is a24 ?
A. 100 B. 85.5 C. 77.5 D. 65 E. 50
OA C
a17 = 250 + (17 - 1)d = 130 or 16d = -120 or d = -15/2
a24 = 250 + (24 - 1)d or a24 = 250 + 23(-15/2) = 250 - 172.5 = 77.5
The correct answer is C.
