If the sum of three numbers in $A.P.,$ is $24$ and their product is $440,$ find the numbers.
Let the three numbers in $A.P.$ be $a-d, a,$ and $a+d$
According to the given information,
$(a-d)+(a)+(a+d)=24$ .........$(1)$
$\Rightarrow 3 a=24$
$\therefore a=8$
$(a-d) a(a+d)=440$ .........$(2)$
$\Rightarrow(8-d)(8)(8+d)=440$
$\Rightarrow(8-d)(8+d)=55$
$\Rightarrow 64-d^{2}=55$
$\Rightarrow d^{2}=64-55=9$
$\Rightarrow d^{2}=\pm 3$
Therefore, when $d=3,$ the numbers are $5,8$ and $11$ and when $d=-3,$ the numbers are $11,8$ and $5$
Thus, the three numbers are $5,8$ and $11 .$
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