The first term of an A.P. is 5, the common difference is 3 and the last term is 80; find the number of terms.
a = 5, d = 3
l = 80
No. of terms, n = 
+ 1
= 
+ 1
= 
+ 1
= 25 + 1
= 26
5
The first term of an A.P. is 5, the common difference is 3 and the last term is 80; find the number of terms.
a = 5, d = 3
l = 80
No. of terms, n = + 1
= + 1
= + 1
= 25 + 1
= 26