Here, we have
a = 8, d = 2, n = 2 and l = 126
We know that,
nth term from the end
= l – (n – 1)d
= 126 – (10 –1)2
= 126 – 18
= 108
The first and the last term of an A .P. are 4 and 81 respectively. If the common difference is 7, how many terms are there in the A .P. and what is their sum?