Question

the first term, common difference and the last term of an AP are 12,6 and 252respectively. find the number of terms

Answer 1

number of term is 41

Answer 2

$an = 252 \\ a = 12 \\ d = 6 \\ n = \\ an = a + (n - 1) \times d \\ 252 = 12 + (n - 1) \times 6 \\ 252 = 12 + 6n - 6 \\ 252 = 6 + 6n \\ 252 - 12 = 6n \\ 240 = 6n \\ n = 240 \div 6 \\ n = 40$
answer 40 it is a value of n