Question

The sum of the 14 terms of an ap is 1050 and its first term is 10. find its common difference

Answer 1

Answer:

a=10

s14=1050

n/2 (2a+(n-1)d) =1050

14/2 (20+(14-1)d)=1050

7(20+13d)=1050

20+13d=150

13d=130

d=10

Answer 2

Answer:

Step-by-step explanation:

Solution:

First term (a) = 10

Sum of 14 terms S-14=1050

Sum of n terms = n/2 (2a+(n-1)d)

So

1050=14/2 (2*10+(14-1)d)

1050=7(20+13d)

1050/7=20+13d

150 =20+13d

13d =130

d=130/13

d=10

Therefore, common difference is 10