Question

the seond term of an ap is 18and its fourth term is 32 write its third and first terms

Answer 1

let a be the first term d be the common difference
given,a2=18
so, a+d=18(i)
and a4=32
so,a+3d=32............(ii)
solving i & ii , we get
d=7 & a=11
therefore first term is 11
third term=a+2d
=11+2*7
=11+14
=25