It's ratio and proportion.
We must find the two number first.
So you said their difference is 48. So you must subtract the two numbers
7 - 4 = 3 (it will be the denominator of the two numbers
Finding x(the first number)
4/3 * 48 = x
Multiply 48 to 4
192/3 = x
Divide
x = 64
Finding y(the second number)
7/3 * 48 = y
Multiply 48 to 7
336/3 = y
Divide
y = 112
Now let's check if their Difference are 48
y - x = 48
112 - 64 = 48 ■ Correct
Now let's add both to know their Sum
112 + 64 = 176
Therefore the sum of the two numbers is 176
I hope it helps.
