collection of tough problems from G PREP - 30

[abhasjha]

At least 100 students at a certain school study Japanese. if 4 % of the students at school who study French also study Japanese, do more students at school study French than Japanese ?

A. 16 students at school study both French and Japanese

B. 10 % of students at school who study Japanese also study French.

[shashank.ism]

At least 100 students at a certain school study Japanese. if 4 % of the students at school who study French also study Japanese, do more students at school study French than Japanese ?

A. 16 students at school study both French and Japanese

B. 10 % of students at school who study Japanese also study French.

Let J be student who study japanese, F who study french and jf who study both
J>100
0.04 F = jf

st 1: jf = 16 --> 0.04 F = 16 --> F= 400 also J>100 but how much we don't know so insufficient.
st 2: 0.1 J = jf , but here we don't know abt french students.. so insufficient

combining both: F= 100, jf =16 ,
0.1 J = jf --> J= 16/0.1 = 160.

so french students a r greater than japanese.


Ans is C