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union and intersection of sets

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union and intersection of sets

by rahul.s » Tue Feb 23, 2010 1:26 am
At Company C, employees who bring lunch each day bring either pasta, a salad, or both. If 10 employees do not bring a lunch each day, how many employees are at the company?

(1) 44 employees bring pasta for lunch each day.
(2) The number of employees who bring a salad each day is equal to the number of employees who bring both a salad and pasta

OA is C, but i opted for E
Source: Knewton

could someone please explain how to solve this one?
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by harsh.champ » Tue Feb 23, 2010 2:34 am
rahul.s wrote:At Company C, employees who bring lunch each day bring either pasta, a salad, or both. If 10 employees do not bring a lunch each day, how many employees are at the company?

(1) 44 employees bring pasta for lunch each day.
(2) The number of employees who bring a salad each day is equal to the number of employees who bring both a salad and pasta

OA is C, but i opted for E
Source: Knewton

could someone please explain how to solve this one?
Let total employees be T ,Pasta-P,Salad -S.
T - (P U S) = 10
St 1:-P = 44 Insuff.
St2:- S = (S n P)
Now,(P U S) = P + S - (P n S)
=>(P U S) = P + S - (P n S)
=>(P U S) = P
Insuff.

Considering both together,
T = 10 + 44 = 54

C is the answer.
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by sumanr84 » Tue Feb 23, 2010 4:51 am
harsh.champ wrote:
rahul.s wrote:At Company C, employees who bring lunch each day bring either pasta, a salad, or both. If 10 employees do not bring a lunch each day, how many employees are at the company?

(1) 44 employees bring pasta for lunch each day.
(2) The number of employees who bring a salad each day is equal to the number of employees who bring both a salad and pasta

OA is C, but i opted for E
Source: Knewton

could someone please explain how to solve this one?
Let total employees be T ,Pasta-P,Salad -S.
T - (P U S) = 10
St 1:-P = 44 Insuff.
St2:- S = (S n P)
Now,(P U S) = P + S - (P n S)
=>(P U S) = P + S - (P n S)
=>(P U S) = P
Insuff.

Considering both together,
T = 10 + 44 = 54

C is the answer.
Nice step-by-step explanation..
I am on a break !!
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by harsh.champ » Tue Feb 23, 2010 5:02 am
sumanr84 wrote:

Nice step-by-step explanation..
Anytime suman. :)
It takes time and effort to explain, so if my comment helped you please press Thanks button :)



Just because something is hard doesn't mean you shouldn't try,it means you should just try harder.

"Keep Walking" - Johnny Walker :P
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