Question

There are ‘n’ AMs between 7 & 71 and 5th AM is 27 then ‘n’ = ______ a) 15 b) 16 c) 17 d) 18

Answer 1

16..

I think........

Answer 2

7, __, __, __, __, 27, ..., 71

27 is the 5th term BEYOND 7, so it's the 6th term

INCLUDING 7. So we begin with n=6

a1 = 7

a6 = 27

an = a1 + (n-1)d

Substitute n=6

a6 = a1 + (6-1)d

27 = 7 + 5d

20 = 5d

4 = d

Now we substitute an = 71

an = a1 + (n-1)4

71 = 7 + (n-1)4

71 = 7 + 4(n-1)

71 = 7 + 4n - 4

71 = 3 + 4n

68 = 4n

17 = n

So there are 17 terms

mark it as a brainliest answer