Question

Find the 12th term from the last of the A.P. 1, 4, 7, 10,.... 88

Answer 1

A.P. 1, 4, 7, 10,.... 88
a=1
d=3
reversing the AP
88,...10,7,4,1
for this AP
a=88
d=-3
n=12
t=88+11*(-3)
=88-33
=55

Answer 2

here d=3
take 88 as first term a &d=-3
now n=12
a12=a+(n-1)d
a12=88+11(-3)
a12=55