Joe took 20 equally weighted quizzes for his biology class and receive

Question

Joe took 20 equally weighted quizzes for his biology class and received an average score of 96% on those quizzes. If he received a grade of 96% on exactly n of the quizzes, what is n?

(1)  n>18

(2)  n\leq20

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Archit3110 · Answer

MM for each test = 10
so for 20 tests ; 200 and 96% . 192
#1 n>18
n has to be 20 ; sufficient
#2
n<=20
insufficient as no of test taken can be with full 10/10 scores as well and n can vary
IMO A

shaliny · Answer

HI, would you please elaborate your solution little bit? what is MM?

Gmat860sanskar · Answer

Hello Shaliny,

MM here is maximum marks.

So for 20 test Maximum one student can secure is 200

and 96 of that total (200) is 192

Statement 1 : n > 18

Ok if total number of test in which he scored 96 percent (n) is above 18 then it could be only one possible case in which this thing is possible, which is n = 20.

Statement 1 is sufficient

Statement 2 : n < = 20

There can be many possibilities i.e n = 20, 15....

So, as there is no definite answer, that's why statement 2 is not sufficient.

Answer - A

KarishmaB · Answer

96% is the average of 20 scores. The actual scores could take infinite different values. It is possible that none of them is 96% and also that all of them are 96%. So n can be anything from 0 to 20. (1) n>18 n can be 19 or 20. But note that if 19 values are 96%, the 20th value cannot be anything other than 96%. For the average to be 96%, if one value is less than 96% then at least one needs to be more than 96% to make up the deficit. This means all 20 values are 96% and n = 20. Sufficient alone. (2) n\leq20 We already know that n is less than or equal to 20. Not sufficient alone. Answer (A) Here is another interesting question on mean, median and range: https://anaprep.com/sets-statistics-mea ... -question/

Joe took 20 equally weighted quizzes for his biology class and receive

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