Question

Find the fourth term of an ap whose first term is 21 and common difference is -3

Answer 1

Answer:

a= 21 , d= -3

an= a +(n-1) d

n= 4

a4 = a+ (4-1) d

a4 = a + 3d

a4 = 21 + 3 (-3)

= 21 - 9

= 12

Hence, the fourth term of an ap is 12