Question

An A. P consists of 31 terms. If it's 16th term is m, then the sum of all the terms of this A. P is

Answer 1

Answer:

Step-by-step explanation:

Answer:

310

Step-bysad-step explanation:

No. of terms= n = 31

16th term = 10

Formula of nth term of AP = a_n=a+(n-1)d

Substitute n = 16

a_{16}=a+(16-1)d

10=a+15d  --A

Sum of n terms = S_n=\frac{n}{2}(2a+(n-1)d)

Substitute n = 31

S_{31}=\frac{31}{2}(2a+(31-1)d)

S_{31}=\frac{31}{2}(2a+30d)

S_{31}=31(a+15d)

Using A

S_{31}=31(10)

S_{31}=310

Hence  the sum of all the terms of this ap is 310