The Sum Of Two Numbers Is 78 And Their Difference Is 30

The problem given says that 2 unknown numbers are given, whose sum is equal to 78 and the difference is 30. Let's find the two numbers :

When we add the two numbers :
X + Y = 78

The difference of two numbers :
X - Y = 30

Solution :

If we add the two equations eachother , then we can find the first number.

X + Y = 78
X - Y = 30

2X = 108

Let's divide 108 to 2 for the first number "X" .

X/2 = 54

First number is 54

X + Y = 78
So ;
54 + Y = 78
Y = 78 - 54
Y = 24

Second number is 24

Question & Answer
The Sum Of Two Numbers Is 78 And Their Difference Is 30 : 54 And 24