The Sum of Two Numbers is 51 and Their Difference is 4

The sum of two numbers is 51 and their difference is 4. 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 51. In other words, x plus y equals 51 and can be written as equation A:

x + y = 51

The difference between x and y is 4. In other words, x minus y equals 4 and can be written as equation B:

x - y = 4

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

x - y = 4
x = 4 + y

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

x + y = 51
4 + y + y = 51
4 + 2y = 51
2y = 47
y = 23.5

Now we know y is 23.5. Which means that we can substitute y for 23.5 in equation A and solve for x:

x + y = 51
x + 23.5 = 51
X = 27.5

Summary: The sum of two numbers is 51 and their difference is 4. What are the two numbers? Answer: 27.5 and 23.5 as proven here:

Sum: 27.5 + 23.5 = 51
Difference: 27.5 - 23.5 = 4

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The Sum of Two Numbers is 51 and Their Difference is 5
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