rahul.s wrote:Foodmart customers regularly buy at least one of the following products: milk, chicken, or apples. 60% of shoppers buy milk, 50% buy chicken, and 35% buy apples. If 10% of the customers buy all 3 products, what percentage of Foodmart customers purchase exactly 2 of the products listed above?
A) 5%
B) 10%
C) 15%
D) 25%
E) 30%
OA: D
Take n (M ∪ C ∪ A) = 100 so that n (M ∩ C ∩ A) = 10.
Now, note:
n (M ∪ C ∪ A) = n (M) + n (C) + n (A) - n (M ∩ C) - n (C ∩ A) - n (M ∩ A) + n (M ∩ C ∩ A)
I know, it is more than GMAT, but, ok...
n (M ∩ C) + n (C ∩ A) + n (M ∩ A) = n (M) + n (C) + n (A) - n (M ∪ C ∪ A) + n (M ∩ C ∩ A) = 60 + 50 + 35 - 100 + 10 = 55.
Take n (M ∩ C ∩ A) = 10, out 3 times of it, to answer what is asked; 55 - 3*10 = [spoiler]
25[/spoiler].
[spoiler]
D[/spoiler]
Last edited by
sanju09 on Sat Jan 30, 2010 5:57 am, edited 2 times in total.
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Sanjeev K Saxena
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The Princeton Review - Manya Abroad
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