Sum of two numbers is 17, whereas sum of their squares is 145. What is the product of the two numbers?
Let the two numbers be $$x$$ and $$y$$
=> Sum = $$x+y=17$$
Squaring both sides, we get : $$(x+y)^2=(17)^2$$
=> $$x^2+y^2+2xy=289$$
Also, it is given that $$x^2+y^2=145$$
=> $$2xy=289-145=144$$
=> $$xy=\frac{144}{2}=72$$
=> Ans - (A)