Question

find the sum of 61 terms of an AP where second and third terms are 14 and 18 respectively
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Answer 1

Answer:

29 is the answer!!!!! (◍•ᴗ•◍)❤(｡♡‿♡｡)

Answer 2

The sum is : 7930

Given in the question

2nd term =>a+d=>14.... i)

3rd term =>a+2d=>18.... ii)

Solving I) and II) we get

a=10

d=4

Now we got that the first term of the AP is 10 and the common difference is +4

Sum of 61 terms of the AP =>

n=61

S=n/2[2a+(n-1)*d]

S=61/2[2*10+(61-1)*4]

S=7930