Question

In an A.P., if the 12th term is - 13 and the sum of
four terms is 24. What is the sum of the first 10
terms ?
.
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Answer 1

Answer:

I hope it will help you.

Answer 2

Answer:

S10=260

Step-by-step explanation:

T12=a+11d=-13.............(1)

S4=4/2*( 2a+3d)=24

2a+3d=12

a+3/2d=6........(2)

Subtracting (2) from(1)

19d/2 =-19

d=-2

and from(1)

a-22=13, a=35

Thus S10=5*(2*35+9*(-2) }

=5*(70-18)

=5*52

=260