Overlapping sets tricky problem

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Overlapping sets tricky problem

by Daniel_reese » Sun Feb 13, 2011 9:02 am
Hey guys what do you think is the answer I would go with D) each statement alone is sufficient? You guys get this too?

Data Sufficiency:
In Jefferson School, 300 students study French or Spanish or both. If 100 of these students do not study French, how many of these students study both French and Spanish?
1) Of the 300 students, 60 do not study Spanish.
2) A total of 240 of the students study Spanish.
Source: — Data Sufficiency |

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by maihuna » Sun Feb 13, 2011 9:32 am
F'=100, F=200
F&U=?

F F'
U x 240
U' 200-x 60
200 100 300

SO E, as both say the same info and not able to find unknown x. E
Daniel_reese wrote:In Jefferson School, 300 students study French or Spanish or both. If 100 of these students do not study French, how many of these students study both French and Spanish?
1) Of the 300 students, 60 do not study Spanish.
2) A total of 240 of the students study Spanish.
Charged up again to beat the beast :)

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by vaflaly » Sun Feb 13, 2011 10:19 am
F number students learning FRENCH
S number students learning SPANISH
noF= number students do not learn FRENCH
noS= number students do not learn SPANISH

noF=100

noF = S - both
noS = F - both
total = F + S - both

total = noF + both + noS + both - both
total = noF + noS + both


1 ---> noS=60

both= total-noF-noS
both= 300 - 100 -60

both=140

SUFFICIENT

2----> S=240

both = S- noF
both = 240-100
both=140

SUFFICENT

So the answer is D

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by Daniel_reese » Sun Feb 13, 2011 10:28 am
Hey,

I would go with vaflaly's answer as well! you get the result in both ways

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by Night reader » Sun Feb 13, 2011 6:30 pm
Daniel_reese wrote:Hey guys what do you think is the answer I would go with D) each statement alone is sufficient? You guys get this too?

Data Sufficiency:
In Jefferson School, 300 students study French or Spanish or both. If 100 of these students do not study French, how many of these students study both French and Spanish?
1) Of the 300 students, 60 do not study Spanish.
2) A total of 240 of the students study Spanish.
&=U (joint below)
there are two distinct sets F (French) and S (Spanish), and one combined set F&S
the problem tells us: F&S+F+S=300, S=100, F&S-?
st(1) F=60, (F&S+F+S) - S - F= F&S OR 300-100-60 = 140; Sufficient.
st(2) 240 study Spanish (may also study French), 300-240=60 study French only; F=60, (F&S+F+S) - S - F= F&S OR 300-100-60 = 140; Sufficient.

answer D :)