Mike, Ron, Debra, and Susie divided a $47 refund so that Mike and Ron together got $27, Mike and Debra got $25, and Mike and Susie got $23. How much did Debra get?

Mike got $14.

Ron got $13.

Debra got $11.

Susie got $9.

One way to get it: *M* + *R* + *D* + *S* = $47.

But *M* + *R* = 27,

*M* + *D* = 25, and

*M* + *S* = 23.

Substituting *R, D,* and *S* in terms of *M* and simplifying, 2*M* = 28, so *M* = 14, and it’s easy from here.

For students who do not have a grip on algebra, here is a nice question that can lead to the solution without using algebra: Notice that 27 + 25 + 23 = 75, which is not 47 — why not? Someone will notice that Mike’s share has been included 3 times, so 75 – 47 = 28 must equal the 2 extra Mike shares. The solution follows easily.