Problem of the Week: In-N-Out Burgers
In-N-Out Burger in the western United States ordinarily sells hamburgers, cheeseburgers, and Double-Doubles (two beef patties and two slices of cheese).
This In-N-Out Burger restaurant is located in Las Vegas, Nevada, where there was a NASA conference. Mr. Durden went in to order and noticed some interesting things about the menu . . .
1. Look at the difference between the cost of the hamburger and the cheeseburger: how much do they charge for a slice of cheese to be added to a hamburger to make it a cheeseburger?
2. Look at the difference between the cost of the cheeseburger and the Double-Double: how much do they charge for the extra beef patty and the extra cheese?
3. Given what you know about the price for the added cheese and added beef patty, how much would it cost for a Double (two hamburger patties on a bun with no cheese)?
(* please note: you can’t just double the menu price for the hamburger)
They also have a secret menu which includes a burger where you can order as many extra beef patties and cheese slices as you like. The most common orders are 3x3′s (Triple-Triples) and 4x4′s (read as “Four by Fours”) that contain three and four layers of beef and cheese, respectively.
However, some people have ordered 20×20′s (like the one above) for special occasions to share as a group and even 100×100’s! The only additions are extra layers of beef patties and cheese.
4. Now that the price patterns are figured out . . .
How much for a 3x3 (Triple-Triple)?
How much for a 20x20 (Twenty by Twenty)?
How much for a 100x100?
Extra Credit--Future Programmers!
In-N-Out just got new portable iPad cash registers: How would you write an equation so the cashier only has to enter the number of beef patties and cheese slices and the app calculates the price?
Extra Extra Credit--Tax Time! If we order a 100x100 for Mr. D.’s SPARK class party, and there is 7.5% sales tax, how much is the tax and how much is the total order?
Logan and Izzy had the same number of stickers. After Izzy gave him 72 stickers, Logan had 3 times as many stickers as Izzy. How many stickers did they have altogether?
1. Read the entire problem
2. Rewrite the question as a statement
3. Who or what is the problem about?
4. Draw your model
5. Write and solve your equation/s
6. Check and fill in your answer (Is it reasonable and accurate?)