There were 28 total trips made, with Andy making 12 of them,
Bart making 5, and Chris making 11. The puzzle can be expressed algebraically as
A + B + C = X, where X is the total number of trips. A = 2.4B. Because A has to
be a whole number (Andy couldn't make 2.4 trips, for example), you quickly find
that 12 and 5 are the lowest possible whole numbers for A and B, which makes C
11. |