find the sum of a series of terms in A.p is 128.if first term is 2 and last term is 14. find d
Answers
Answered by
2
sum=n/2(a+l)
128=n/2(2+14)
128×2/16=n
8×2=16=n
so number of terms in this question are 16.
last term=a+(n-1)d=2+15d=14
15d=12
d=12/15=4/5
show the difference is 4 /5....
hope it helps
128=n/2(2+14)
128×2/16=n
8×2=16=n
so number of terms in this question are 16.
last term=a+(n-1)d=2+15d=14
15d=12
d=12/15=4/5
show the difference is 4 /5....
hope it helps
Similar questions