AS #64

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AS #64

by oquiella » Sun Oct 25, 2015 3:28 pm
64. A survey of all the 100 employees in an organization revealed that 50% take tea and
50% take coffee. How many employees in the organization take neither tea nor
coffee?


(1) 25 employees take both tea and coffee.
(2) The survey included only those employees who take either tea or coffee.
Source: — Data Sufficiency |

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by theCEO » Sun Oct 25, 2015 5:00 pm
oquiella wrote:64. A survey of all the 100 employees in an organization revealed that 50% take tea and
50% take coffee. How many employees in the organization take neither tea nor
coffee?


(1) 25 employees take both tea and coffee.
(2) The survey included only those employees who take either tea or coffee.
All the employees in the organization participated - 100 total
50% take tea = 0.5 x 100 = 50 for tea
50% take coffee = 0.5 x 100 = 50 for coffee

How many employees in the organization take neither tea nor coffee?

1) 25 employees take both tea and coffee
Therefore 50 - 25 = 25 take tea only
Therefore 50 - 25 = 25 take coffee only
Summing all these employees we get 25+25+25 = 75
employees in the organization take neither tea nor coffee = 100 - 75 = 25
Statement is sufficent

2) The survey included only those employees who take either tea or coffee
If survey was done on all employees and included those who take either tea or coffee,
It means no one took both tea and coffee.
It also mean no one takes neither tea nor coffee
Statement is sufficent

ans = d

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by Matt@VeritasPrep » Sun Oct 25, 2015 10:27 pm
Tea + Coffee - Both + Neither = Total

From the prompt, we know that Tea = 50, Coffee = 50, and Total = 100. This gives us

Neither - Both = 0

or

Neither = Both

S1:: Both = 25; SUFFICIENT
S2:: Neither = 0; SUFFICIENT

(S2 is actually more problematic than it looks, but I've interpreted it as I think it was MEANT to be written: "All 100 employees drink either tea or coffee.")