The Sum of Two Numbers is 81 and Their Difference is 1

The sum of two numbers is 81 and their difference is 1. What are the two numbers? Let's start by calling the two numbers we are looking for x and y.

The sum of x and y is 81. In other words, x plus y equals 81 and can be written as equation A:

x + y = 81

The difference between x and y is 1. In other words, x minus y equals 1 and can be written as equation B:

x - y = 1

Now solve equation B for x to get the revised equation B:

x - y = 1
x = 1 + y

Then substitute x in equation A from the revised equation B and then solve for y:

x + y = 81
1 + y + y = 81
1 + 2y = 81
2y = 80
y = 40

Now we know y is 40. Which means that we can substitute y for 40 in equation A and solve for x:

x + y = 81
x + 40 = 81
X = 41

Summary: The sum of two numbers is 81 and their difference is 1. What are the two numbers? Answer: 41 and 40 as proven here:

Sum: 41 + 40 = 81
Difference: 41 - 40 = 1

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The Sum of Two Numbers is 81 and Their Difference is 2
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