On a recent trip to Ohio, my wife and I stopped at a Drive-In restaurant called Swensons. The Menu advertised 17 flavors of milkshakes which were available in two sizes. For an additional 15 cents, you could combine any two flavors.
How many different milkshakes does Swensons serve? Consider a regular chocolate shake different from a small chocolate shake.
Solution to Problem:
The answer is 306 milkshakes.Bob Hearn sent in the following answer:
First, there are 17 different one-flavor milkshakes,
but they can be ordered in two different sizes. This
gives 34 different one-flavor shakes.
To determine the number of two-flavor milkshakes,
take the combination of 17 flavors taken two at a time.
This yields 136 but again they can be ordered in two different
sizes. Hence, there are 272 different two-flavor shakes which
can be ordered.
So the total number of different milkshakes which Swensons makes
is 34 + 272 = 306 !!!
Correctly solved by:
1. Walt Arrison | Philadelphia, Pennsylvania |
2. Mr. and Mrs. William Funk | San Antonio, Texas |
3. David & Judy Dixon | Bennettsville, South Carolina |
4. Rick Jones | Kennett Square, Pennsylvania |
5. Wayne Price | Beatrice, Nebraska |
6. Matt Stillwagon | Winchester, Virginia |
7. Richard Johnson | La Jolla, California |
8. Bobby Martin | Columbus, Georgia |
9. James Alarie | University of Michigan -- Flint Flint, Michigan |
10. Tina Zahel | Winchester, Virginia |
11. Keith Mealy | Cincinnati, Ohio |
12. Bob Hearn | Winchester, Virginia |
13. Ben Reames | Columbus, Georgia |
14. Ashley Neumann | Winchester, Virginia |
15. Pam Coffield | Columbus, Georgia |
16. Jeffrey Gaither | Winchester, Virginia |
17. Michael Rodriguez | Great Falls, Montana |