The sum of the two numbers is 30 and their difference is 20. What are the two numbers?

Solution:

Given sum of two numbers is 30 and difference of them is 20

Let the two numbers be x, y

So, x + y = 30 --- (a)

x - y = 20 --- (b)

Let us solve this system of linear equations.

Add (a) and (b), we get

(x + y) + (x - y) = 30 + 20

2x = 50

x = 25

Put x = 25 in either (a) or (b)

25 - y = 20

y = 25 - 20

y = 5

Therefore, the two numbers are 25, 5

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The sum of the two numbers is 30 and their difference is 20. What are the two numbers?

Summary:

The sum of the two numbers is 30 and their difference is 20, the two numbers are 25, 5.