Of course, you can have some help.
This problem we want to think of a system of equations. Let's say that Joe's earnings are "J" and Mickey's Earnings are "A"
Can you write 2 equations to represent their earnings? Try it before you keep reading.
Here's what the equations should look like:
Since we have 2 equations and 2 unknown variables, this is a solvable system. Since we know what J is (J=3*M), we can substitute the J in the second equation with 3*M. Let's do that.
(3*M) + M = 210
Now we can solve for M.
3M+M=210 (3M plus M is equal to 4M)
4M = 210 (Let's divide both sides by 4)
This means that Mickey earned $52.50 over the summer. We can use that to find out how much Joe made by substituting M=52.50 into equation 1.
1) J= m * 3
This means Joe earned $157.50 during the summer. Let's make sure we didn't make a mistake by plugging J=157.5 and M=52.5 into equation 2.
Since both sides are equal, we know that our answers are right!