Suppose the two numbers are:
first number=x
second number=y
So
equation 1:
X-3=4y
equation 2:
X+Y=102
equation 2 can also be written as:
x=102-y
substituting this into equation 1:
102-y-3=4y
Subtracting:
99-y=4y
Shifting y to the other side:
99=4y+y
99=5y
Dividing:
y=99/5
So:
y=19.8
For x:
x=102-y
Substituting:
x=102-19.8
Subtracting:
x=82.2
So the two numbers are 19.8 and 82.2
first number=x
second number=y
So
equation 1:
X-3=4y
equation 2:
X+Y=102
equation 2 can also be written as:
x=102-y
substituting this into equation 1:
102-y-3=4y
Subtracting:
99-y=4y
Shifting y to the other side:
99=4y+y
99=5y
Dividing:
y=99/5
So:
y=19.8
For x:
x=102-y
Substituting:
x=102-19.8
Subtracting:
x=82.2
So the two numbers are 19.8 and 82.2