Find the sum of first 22 terms of an A.P. in which d = 22 and a22 = 149.
a22= a + 21d
149 = a + 21(22)
a = 149 – 462
a = -313
S22= 
[2a + (22 – 1) d]
= 11 [-626 + 462]
= 11 (-164)
= -1804
10
Find the sum of first 22 terms of an A.P. in which d = 22 and a22 = 149.
a22= a + 21d
149 = a + 21(22)
a = 149 – 462
a = -313
S22= [2a + (22 – 1) d]
= 11 [-626 + 462]
= 11 (-164)
= -1804