Question

in an ap if the 12 th term is -13 and the sum of four terms if 24 find the sum of its first ten terms​

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

0

Step-by-step explanation:

Before going to question,

lets find out the concept of the question!!

ARITHMETIC PROGRESSIONS.

what us an A.P

Arithemetic progression is an series of number by which they onlh differ by common difference.

are are of the form.

a,a+d,a+2d,...(a+(n-1)d)...

Now,

coming to the question,

IT IS GIVEN THAT,

a+11d= -13------(1)

and

a+a+d+a+2d+a+3d=24

=>4a+6d=24

=>2a+3d=12------(2)

Using (1) and (2).

d= -2

a=9

and now,

what is the sum of first 10 terms!!

Sn=n/2(2a+(n-1)d)

Sn=5(2.9+9.(-2))

Sn=5(18-8)

Sn=5x0

Sn=0.

therefore,

sum to first ten terma of A.P

is 0.

ANS.

THANKS!!