GRE Math Problem 50

A vegetarian sandwich shop has a choice of 4 different sandwich toppings.

Column A	Column B
The number of different types of sandwiches that can be made if at least one topping has to be used and each topping cannot be used more than once.	32

Solution for GRE Math Problem 49:
There is the possibility for m=5 ,n=5, thus m=n. But there also can be m=1, n=25 and m
In general, the relation is unknown.
Answer:D

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