Question

the sum of first 45 terms of an AP is 3150 .find its 23rd term ​

Answer 1

Answer:

the answer is 70

Step-by-step explanation:

sum of first 45 terms=45{2a+(45-1)d}/2

3150=45(2a+44d)/2

3150/45=2(a+22d)/2

70=a+22d

a+(23-1)d=70

Therefore, 23rd term=70

Answer 2

Step-by-step explanation:

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

by question

n/2(2a+(n-1)d)=3150

45/2(2a+(45-1)d=3150

2a+44d=3150×2/45

2a+44d=70×2

2a+44d=70×2

2(a+22d)=70×2

a+22d=70........(1)

23rd term =a+(n-1)d

a+(23-1)d

23rd term =a+22d

23rd term =70..........by =n (1).

70