Find the whole number which when decreased by 20 is equal to 69

Solution:

Let the whole numbers be x.

Then according to question

$(x-20)=69 \times \frac{1}{x}$

$x(x-20)=69$

$x^{2}-20 x-69=0$

$x^{2}-23 x+3 x-69=0$

$x(x-23)+3(x-23)=0$

$(x-23)(x+3)=0$

$(x-23)=0$

$x=23$

Or

$(x+3)=0$

$x=-3$

Since, whole numbers being a positive, so x cannot be negative.

Thus, whole numbers be