Forums

Back

Sequence and series

Maths & Stats

The sum of the first 3 terms in AP is 18 and that of the last 3 is 28, if the AP has 13 terms, what is the sum of middle three terms? A. 23 B. 18 C. 19 D. None of the above

Krishna Dholariya

CA Inter

★ 33K+

22-Nov-21 11:47

607

Answers (6)

3a+3d=18 equation 1 3a+33d=28 equation 2 - - - -30d=-10 d=1/3 now find a by using d Then find middle term 5,6,7

Dhakshana Dhakshana

CFA L2

★ 18K+

22-Nov-21 13:05

OK thank you

Thread Starter

Krishna Dholariya

CA Inter

★ 33K+

22-Nov-21 13:18

Thread Starter

Krishna Dholariya

OK thank you

Did u get the ans

Dhakshana Dhakshana

CFA L2

★ 18K+

22-Nov-21 13:18

Yes

Thread Starter

Krishna Dholariya

CA Inter

★ 33K+

22-Nov-21 13:19

Thread Starter

Krishna Dholariya

Yes

Oki

Attachments

Dhakshana Dhakshana

CFA L2

★ 18K+

22-Nov-21 13:23

OKk thanks for explain

Thread Starter

Krishna Dholariya

CA Inter

★ 33K+

22-Nov-21 13:28