Question

Find the common difference of the A.P with first term $-18$, nth term $0$ and number of terms $10$

Answer 1

We have,

$T_n=0,a=-18,n=10,d=?$

We know that

$T_n=a+(n-1)d$

$0=-18+(10-1)d$

$18=9\times d$

$d=2$

Hence, the common difference is $2$.