The Infinite House of Pancakes (IHOP) offers 35 different kinds of pancakes. You would like to order a stack of three pancakes. How many different choices do you have, considering that you care about the order in which the pancakes are stacked? (In other words, pecan/blueberry/pecan is a different choice from pecan/pecan/blueberry.) (a) P(35,3) (b) 75 (c) 35^3 (d) 3^35 (e) C(35,3) (f) none of the above
a. If the problem says order, you use permutations.
My professor said that the answer is C. I originally got A as the answer too. I have no idea how he got his answer.
C is correct: You have 35 choices for first stack, 35 choices for second stack, and 35 choices for third, therefore total choices you have is \(\boxed{35^3}\)
That makes sense! Thanks. How do I know when do that method or to use permutation?
when to do*
Basically, if repetition is allowed, you just multiply by how many choices you have, etc. Permutation or combinations is used when repetition is not allowed, depending on whether order matters or not.
If your problem says that you cannot select same pancake more than one times, then answer would be A.
Ah, okay! I understand!
Thanks again :)
No problem
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