Q) How many terms are there in an A.P. whose first and fifth terms are -14 and 2, respectively and the last term is 62.
Ans: Let’s consider an A.P with first term as N1 and common difference as ‘d’.
Next, we know that nth term of an A.P. = a + (n-1) d
here, a = first term,
n = total no. of terms till nth term
d = common difference between any two terms
Therefore, 1st term, N1 = a = -14 (given)
and 5th term, N5 = -14 + 4d = 2 (given)
d = 4
Now we are given that 62 is the last term.
if 62 is the nth term, then:
62 = -14 + (n-1) 4
n = 20
Therefore, there are 20 terms in the given A.P.