Out of total 36 students in a class, what percent of students passed
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08 Jun 2018, 17:04
To find: The percent of students that passed the exam. Or we can find the number of students that passed the exam, which will also give us the answer.
Statement 1
\(\frac{7}{10}\) of boys passed. So number of boys has to be a multiple of 10.
Possible number of boys: 10,20,30. Those are all the possibilities. Next multiples of 10 will exceed the total number, 36.
12.5% of girls passed. You should know by heart that this is \(\frac{1}{8}\). So number of girls has to be a multiple of 8.
Possible number of girls: 8,16,24,32. Those are all the possibilities. Next multiples of 8 will exceed the total number, 36.
To summarize,
Possible number of boys: 10,20,30.
Possible number of girls: 8,16,24,32.
You can quickly scan these 2 sets to see which number of boys and which number of girls will sum to 36. Only boys=20 and girls=16 works. We found the number of boys in the class and the number of girls in the class, thus can find how many passed.
Sufficient
Statement 2
No info about how many passed.
Not sufficient
Answer: A