Question

First term of an ap is 10,000 and common difference is 2000 find sum of first 12th term

Answer 1

A=10000
d=2000
sum of 12 terms =Sn=
$n \div 2(2a + (n - 1)d)$
$12 \div 2(2 \times 10000 + (12 - 1)2000$
$6(20000 + 22000)$
$6 \times 42000 = 256000$
the sum of first 12 terms is 256000
thank you