The Sum of Two Numbers is 81 and Their Difference is 3

The sum of two numbers is 81 and their difference is 3. 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 3. In other words, x minus y equals 3 and can be written as equation B:

x - y = 3

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

x - y = 3
x = 3 + y

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

x + y = 81
3 + y + y = 81
3 + 2y = 81
2y = 78
y = 39

Now we know y is 39. Which means that we can substitute y for 39 in equation A and solve for x:

x + y = 81
x + 39 = 81
X = 42

Summary: The sum of two numbers is 81 and their difference is 3. What are the two numbers? Answer: 42 and 39 as proven here:

Sum: 42 + 39 = 81
Difference: 42 - 39 = 3

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The Sum of Two Numbers is 81 and Their Difference is 4
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