The avg test score on the final exam for students of class period A was 86. On the same exam, the avg test score for students in class period B was 74. Were there more students in class period A than in B?
a) The no. of students in class period A that scored an 86 on the finals was the same as the no. of students in class period B who scored 74 on the final exam.
b) The avg score for all the students in class periods A & B was 81.
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cypherskull
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Statement 1: The no. of students in class period A that scored an 86 on the final was the same as the no. of students in class period B who scored 74 on the final exam.cypherskull wrote:The avg test score on the final exam for students of class period A was 86. On the same exam, the avg test score for students in class period B was 74. Were there more students in class period A than in B?
a) The no. of students in class period A that scored an 86 on the finals was the same as the no. of students in class period B who scored 74 on the final exam.
b) The avg score for all the students in class periods A & B was 81.
No information about the other students in each class.
INSUFFICIENT.
Statement 2: The avg score for all the students in class periods A & B was 81.
When the classes are combined, the average (81) is closer to the average in class A (86) than to the average in class B (74).
Thus, the number of students in class A must be greater than the number of students in class B: if there are more values yielding an average of 86 than there are values yielding an average of 74, the average when the classes are combined will be closer to 86 than to 74.
SUFFICIENT.
The correct answer is B.
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Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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bighnarajeast
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Can you please describe brefely that why you say -- "When the classes are combined, the average (81) is closer to the average in class A (86) than to the average in class B (74).Thus, the number of students in class A must be greater than the number of students in class B".
What's the rule behind this ?
What's the rule behind this ?
