Arithmetic Mean(2)

[tsmith93]

If 25 students took a quiz, the grades they earned ranged from 2 to 10. If exactly 22 of them passed, by earning a grade of 7 or higher, what is the highest possible average (arithmetic mean) the class could have earned on the quiz?

[ajith]

If 25 students took a quiz, the grades they earned ranged from 2 to 10. If exactly 22 of them passed, by earning a grade of 7 or higher, what is the highest possible average (arithmetic mean) the class could have earned on the quiz?

The highest possible average is when all the 22 people who passed have a grade of 10 and all who failed have a grade of 6

The highest possible average = (22*10 +3*6)/ 25 = 9.52

[harsh.champ]

If 25 students took a quiz, the grades they earned ranged from 2 to 10. If exactly 22 of them passed, by earning a grade of 7 or higher, what is the highest possible average (arithmetic mean) the class could have earned on the quiz?

For the highest possible AM,the all the 22 students will get grade 10.
Also,the 3 students who failed will have a grade of 6.

Hence,answer would be (22 x 10 + 3 x 6)/25 = 9.52

[shashank.ism]

If 25 students took a quiz, the grades they earned ranged from 2 to 10. If exactly 22 of them passed, by earning a grade of 7 or higher, what is the highest possible average (arithmetic mean) the class could have earned on the quiz?

the max average is possible if 22 out of 25 gets a grand 10 and 3 out of 25 gets a phenomenal 6
so highest possible average = (22x10 + 3 x 6)/25 = (220 + 18)/25 = 9.52

[susanaryal]

No, its 9.36 because the question says the grades range from 2 to 10 so we have to include 2 for atleat a person whi failed too..
so max average possible is: (22×10+2×6+2×1)/25 = 9.36

[[email protected]]

Hi susanaryal,

I agree with your general interpretation of the prompt, but this is a badly-worded question. Based on the first sentence, it certainly seems like someone scored a 2, but it could also be that the POSSIBLE scores are in the range of 2 to 10, inclusive (meaning that 2 is the lowest possible score that one could earn). We're also NOT told if the scores are all INTEGERS. For example, scoring a failing score of 6.9 (instead of a 6) would end up changing the group average.

Whatever the source was for this question (keep in mind, the original post is from 2010), the prompt isn't written in proper GMAT 'style' (and doesn't include the 5 answer choices), so you can ignore it. You'll find far more realistic material to work with in other, more modern, sources.

GMAT assassins aren't born, they're made,
Rich

[nikhilgmat31]

it depends on the 5 answers & whether score can be in decimals.

(6 * 3 + 10 * 22)/25 = 9.52
(6.99 * 3 + 10 * 22)/25 = 9.63