Question

The difference of two numbers is 72. And their sum is 145.
What are those two numbers?

Answer 1

Answer:

Hint:The sum is a+b. The difference is a-b. Adding the sum to the difference is (a+b) + (a-b) which is a + b + a - b = 2a. So you see that half of this is one of the original numbers (a).

Step-by-step explanation:

The sum is a+b. The difference is a-b. Adding the sum to the difference is (a+b) + (a-b) which is a + b + a - b = 2a. So you see that half of this is one of the original numbers (a).

Answer 2

Answer:

Letthenumbersbexandy,thenx−y=72

and(

y

x

)=3

orx=3y

∴3y−y=72

2y=72

∴y=36,thenx=108