Question

Michael is 4 times as old as Brandon and is also 27 years older than Brandon. How old is Michael?

Answer 1

Let M mean Michael, and B mean Brandon, when write two equations:

M = 4B
B = M - 27

Replace the B in the first equation with what it is equal to in the second equation:
M = 4(M - 27)
Distribute
M = 4M - 108
Subtract 4M from both sides
-3M = -108
M = 36

Now put that back into the equation for B.
B = M - 27
B = 36 - 27
B = 9

So, Brandon is 9 and Michael is 36.