Question

The sum of two numbers is 46 and their

difference is 20. What is the smaller
number?
1
A) 40
B) 13
C) 26
D) 12

Answer 1

B. 13

Explanation:

We have two unknown numbers, let's have two variables for these two unknown numbers, X and Y.

"The sum of two numbers is 46 and their difference is 20."

Meaning we have two equations :

X + Y = 46

X - Y = 20

Looking at the last part of "their difference is 20." We can assume X = Y + 20

So substitute the assumed equation into X + Y = 46

(Y + 20) + Y = 46

2y + 20 = 46

Subtract 20 from both sides :

2y = 26

Divide 2 by both sides :

y = 13

There you go.

Answer 2

46/2 is 23
20/2 is 10
The number is + or - 23
So 13 and 33
13