PR - pizza combinations

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PR - pizza combinations

by jayhawk2001 » Mon May 28, 2007 2:23 pm
Another interesting DS question. OA after a few reply.

Beth’s pizzeria offers x different toppings. What is the value of x?

(1) There are an equal number of different pizzas that can be made with (x − 2) toppings as there are different pizzas with just 2 toppings.

(2) If the pizzeria were to add one additional topping, the number of different pizzas that could be made with 4 toppings would double.

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by Neo2000 » Mon May 28, 2007 7:30 pm
Good useage of combinations

From statement 1
(X-2) = XC2
Not solveable

From Statement 2
(2XC4) = (X+1)C4
This is solveable you get X = 2

Hence Statement 2 alone

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Re: PR - pizza combinations

by gviren » Wed May 30, 2007 5:38 pm
I think the answer is D

1) The # of pizza for n toppings would be 2^n.
so 2^(x-2) = 2^2
x-2=2
x=4

2) 2^(x+1) = 2 X 2^4 = 2^5
x+1 = 5
x=4

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by jayhawk2001 » Wed May 30, 2007 5:43 pm
Good one Neo.

OA is B.