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Question

The sum of two numbers is 138. One number is 20 less than the other. Find the number

Answer 1

x + x -20 = 138

2x - 20 = 138

2x = 158

x = 79

Answer 2

Let the two numbers be X and Y respectively

X + Y = 138

X - Y = 20

Let's add the two equations we get,

2X = 158

X = 79

Substituting the value of X in any of the first two equations gives us Y as 59

Your two numbers are 79 and 59