Question

Question 3 (iii)
In the following APs, find the missing term in the boxes.
(iii) $5,\square ,\square ,9\frac{1}{2}$

Answer 1

For this A.P.,
a = 5
$a_4=9\frac{1}{2}=\frac{19}{2}$
We know that,
$a_n=a(n-1)d$
$a_4=a+(4-1)d$
$\frac{19}{2}=5+3d$
$\frac{19}{2}-5=3d$
$\frac{9}{2}=3d$
$d=\frac{3}{2}$
$a_2=a+d=5+\frac{3}{2}=\frac{13}{2}$
$a_3=a+2d=5+2\left(\frac{3}{2}\right)=8$
Therefore, the missing terms are $\frac{13}{2}$ and 8 respectively.