Of 200 people surveyed, 80 percent own a cellular phone and 45 percen

My option E)

Straight forward answer if you follow 2x2 matrix method..

cell , not cell

Pag - - 90

N. pag - - 110

160 40 200

Required = 110+90 = 150
therefore, 150/200 = 75%.

redundant information.
we do not need the number 200 to find oa is e.

n ( C ∪ P ) = n ( C ) + n ( P ) - n ( C ∩ P )

200 = 160 + 90 - n ( C ∩ P )

Or, n ( C ∩ P ) = 250 - 200

Or, n ( C ∩ P ) = 50

So, Percentage of people owning both a Cell Phone & Pager is 25% and 75% owns a Cell Phone + Pager...

Thus , 75% either do not own a cellular phone or do not own a pager..

Hence, answer will be (E)...

We know : T (total) - N (neither)= A + B - K(both)
Total : 100% (given)
Neither : 0 % (given)

100- 0 = 80 + 45 + K
=> K = 125-100= 25

Now we know that A= A1 + K i.e. A= Own cellular phone, K = own cellular phone and pager, A1= own's cellular phone only and not pager , => 80=A1 + 25 =>A1= 55
Similarly B=B1 + K, => B1= 20

So A1 + B1 = 55+20 = 75

Ans : E

The 80% (160) that own a cell phone and 45% (90) that own a pager also include those that own both. If c=cell phone owners only, p=pager owners only and b=both, then: Total=(c+b)+(p+b)-b
So, 200=160+90-b
b=50, so 150 own only one of either a pager or cell. 75%.

If you like and/or agree then kudos. If you have a better method, please comment!

80% own cell phone, 20% do not.
45% own pager, 55% do not.
So percent of those who either do not own cell phone or do not own pager is 20% + 55% = 75%

Hi All,

This question is a modified version of a typical Overlapping Sets question. You can solve it with the tic-tac-toe board or the Overlapping Sets Formula:

Total = (Group 1) + (Group 2) - Both + Neither

In this prompt, we're told that ALL 200 people own at least one of the two items, so the 'Neither' group would be 0.

80% of 200 = 160 people own a cell phone
45% of 200 = 90 people own a pager

Plugging that data into the formula, we have...

200 = 160 + 90 - Both

200 = 250 - Both
Both = 50

Since 50 of the 200 people have both items, the other 200 - 50 = 150 people have just one item. As a percentage of the total, that is 150/200 = 75%

Final Answer:

GMAT assassins aren't born, they're made,
Rich

HI Bunuel, niks18, Gladiator59,

either do not own a cellular phone or do not own a pager Does it mean only a cellular phone and only pager?

Hi NandishSS

yes your understanding is correct. You can visualize the question as

Those who do not own cellular phone = Those who own pagers only

Those who do not own pager = Those who own cellular phones only

So those who do not own a cellular phone or a pager = Those who own only cellular phone + those who own only pager

We can use the formula for overlapping sets for this problem:

Total = #Cell + #Pager - Both + Neither

200 = 160 + 90 - x + 0

200 = 250 - x

50 = x

We see that 50 individuals own both a cell phone and a pager. Thus, the number of people who own a cell phone and not a pager is 160 - 50 = 110.

Similarly, of the 90 individuals who own a pager, there are 90 - 50 = 40 who own a pager and not a cell phone.

Thus, there are 110 + 40 = 150 who either do not own a cell phone or do not own a pager.
This number represents 150/200 = 3/4 x 100% = 75% of the people surveyed.

Answer: E

We don't need to use the actual numbers since we need a percent as our answer, saving us some calculations.

Most efficient way to do this Q is to use a double-set matrix as shown in the attachment.

"either do not own a cellular phone or do not own a pager" => ~C + ~P = 20 + 55 = 75%

ANSWER: E

I don't know why all answers were extremely complicated, this is the simplest solution.

80% own a cell phone, so 20% do not own a cellphone.
45% own a pager, so 55% do not own a pager
20%+55%=75%

Percent who do not own a cellular phone = 100 - 80 = 20%
Percent who do not own a pager = 100 - 45 = 55%
Percent of those surveyed either do not own a cellular phone or do not own a pager = 20 + 55 = 75%

Hence, the OA is (E).

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