Let's call the smaller number "x" and the larger number "y." Since 7 is added to the larger number, y + 7 = 4x. Since 28 is added to the smaller number, x + 28 = 2y.
We can solve this system of equations by substituting the first equation into the second equation to eliminate one of the variables:
x + 28 = 2(y + 7)
x + 28 = 2y + 14
x - 2y = -14
Then, we can substitute the second equation into the first equation to eliminate the other variable:
y + 7 = 4(x + 28)
y + 7 = 4x + 112
y - 4x = -105
Now we have a system of two equations in two variables, which we can solve using methods such as substitution or elimination. Let's use substitution:
x - 2y = -14
y - 4x = -105
If we solve the second equation for y, we get y = 4x - 105. Substituting this expression into the first equation gives:
x - 2(4x - 105) = -14
x - 8x + 210 = -14
-7x = -224
x = 32
Substituting this value back into the expression for y gives us y = 4(32) - 105 = 107.
Therefore, the two numbers are x = 32 and y = 107. If 7 is added to the larger number, the value obtained is 107 + 7 = 114, which is four times the smaller number (32). If 28 is added to the smaller number, the value obtained is 32 + 28 = 60, which is twice the larger number (107).