If each of the students in a certain mathematics class is either a junior or a senior, how
many students are in the class?
(1) If one student is to be chosen at random from the class to attend a conference,
the probability that the student chosen will be a senior is 4/7.
(2) There are 5 more seniors in the class than juniors
OA C
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hrishikesh05
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Class= J(jrs)+S(srs)
(1) S= 4/7 of the total, so S/(S+J)=4/7. INSUFF
(1) S=J+5. INSUFF
(1)+(2) S/(S+J)= 4/7 (1)
Replacing (2) into (1)
(J+5)/(J+(J+5))=4/7
SUFF
Answer C
There are 15 Junior and 20 Senior students in the class. Total q is 35
(1) S= 4/7 of the total, so S/(S+J)=4/7. INSUFF
(1) S=J+5. INSUFF
(1)+(2) S/(S+J)= 4/7 (1)
Replacing (2) into (1)
(J+5)/(J+(J+5))=4/7
SUFF
Answer C
There are 15 Junior and 20 Senior students in the class. Total q is 35
