Members?

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Members?

by grandh01 » Wed Aug 15, 2012 4:44 pm
Thirty percent of the members of a
swim club have passed the lifesaving
test. Among the members who have not
passed the test, 12 have taken the
preparatory course and 30 have not
taken the course. How many members
are there in the swim club?
(A) 60
(B) 80
(C) 100
(D) 120
(E) 140

OA is B
Source: — Problem Solving |

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by theCEO » Wed Aug 15, 2012 5:38 pm
The correct answer is (a)

70% of people = 12 + 30
100% of people = (100/70)*42 = 60

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by alex.gellatly » Wed Aug 15, 2012 6:21 pm
grandh01 wrote:Thirty percent of the members of a
swim club have passed the lifesaving
test. Among the members who have not
passed the test, 12 have taken the
preparatory course and 30 have not
taken the course. How many members
are there in the swim club?
(A) 60
(B) 80
(C) 100
(D) 120
(E) 140

OA is B
I agree the answer should be A and not B. This is because:
if n is the total number of members than;
.30n passed the test and .70n failed the test.

of the .70n people 12 people have taken the class and 30 have not taken the class
that means that 30+12= 42 people is .70n. so solve for n
.70n=42
n=60
A useful website I found that has every quant OG video explanation:

https://www.beatthegmat.com/useful-websi ... tml#475231

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by grandh01 » Thu Aug 16, 2012 10:27 am
I got the same answer, must be a typo thanks guys.