If 7th and 13th terms of an AP be 34 and 64, then its 18th term is :
We know that,
xm−xn=(m−n)d
∴x13−x7=(13−7)d
64−34=6d
30=6d
⇒d=5
18th term is
x18=x13+5d
x18=64+5(5)
x18=64+25=89
If the 7th and 13th terms of an AP are 34 and 64 respectively, then its 18th term would be ____
If the 7th and 13th terms of an AP are 34 and 64 respectively, then the 18th term of the AP would be ___.