In a certain class, some students donated cans of food to a local food

Question

In a certain class, some students donated cans of food to a local food bank. What was the average (arithmetic mean) number of cans donated per student in the class?

(1) The students donated a total of 56 cans of food.
(2) The total number of cans donated was 40 greater than the total number of students in the class.

NEW question from GMAT® Official Guide 2019 
(DS03138)

doomedcat · Accepted Answer

average (arithmetic mean) number of cans donated per student =   \frac{Number of cans donated (C)}{Number of Students (X)}

1) As we are not given number of students who donated, hence Not Suff

2) Cans = total students + 40, so the equation becomes   \frac{(X+40)}{X}  ,Not Suff

1) + 2) from 1) we have C=56, from 2) C=40+X ==> 56=40+X ==> X= 16,
now we can find   \frac{C}{X}   =   \frac{56}{16}   = 3.5

Hence , C

EgmatQuantExpert · Answer

Solution

Given:  
 • In a certain class, some students donated cans of food to a local food bank

To find:  
 • The average (arithmetic mean) number of cans donated per student in the class

Analysing Statement 1  
 • As per the information given in statement 1, the students donated a total of 56 cans of food
• To find the average, we also need to know the number of students in the class
 o As this information is not given, we cannot find out the average contribution

Hence, statement 1 is not sufficient to answer

Analysing Statement 2  
 • As per the information given in statement 2, the total number of cans donated was 40 greater than the total number of students in the class
 o If we assume the total number of students to be n, then the number of cans donated will be (n + 40)
o The average contribution per student =  \frac{n + 40}{n}  =  1 + \frac{40}{n}  
• As we don’t know the value of n, we can’t find out the average

Hence, statement 2 is not sufficient to answer

Combining Both Statements  
Combining both the statements, we can say:
 • If there are n students, total number of cans donated will be n + 40, which is equal to 56
 o Therefore, n = 16 
• As we know the total number of students and the total number of cans donated, we can find out the average donation per student.

Hence, the correct answer is option C.

Answer: C

chetan2u · Answer

We are to just find info is enough to answer..

What do we require for average
1) total cans - C
2) total students- S

Let's what info each equation gives..
(1) The students donated a total of 56 cans of food.
C=56
Gives us C, but S NOT known
Insufficient
(2) The total number of cans donated was 40 greater than the total number of students in the class.
C=40+S
Only a linear equation in two variables
Insufficient

Combined
Two linear equation with 2 unknowns
Sufficient

C

avigutman · Answer

Video solution from Quant Reasoning: Subscribe for more: https://www.youtube.com/QuantReasoning? ... irmation=1 https://www.youtube.com/watch?v=DWOQ7HWOB8A

safeara · Answer

I thought mean was all the numbers added together divided by the number of terms?

GMATinsight · Answer

Answer: Option C

Video solution by  GMATinsight

https://www.youtube.com/watch?v=kS7d6zRQ5sc

ScottTargetTestPrep · Answer

Solution:
 
 Question Stem Analysis:

We need to determine the average number of cans of food donated per student in the class.

Statement One Alone:

Although we know the total number of cans of food donated, we don’t know the number of students in the class, and thus we can’t determine the average number of cans of food donated per student in the class. Statement one alone is not sufficient.

Statement Two Alone:

Although we know that the total number of cans donated was 40 greater than the total number of students in the class, we know neither the total number of cans donated nor the number of students in the class. Thus, we can’t determine the average number of cans of food donated per student in the class. Statement two alone is not sufficient.

Statements One and Two Together:
 
With the two statements, we see that a total of 56 cans were donated, and the number of students in the class was 56 - 40 = 16. Thus, the average number of cans donated was 56/40 = 7/5 = 1.4. The two statements together are sufficient to answer the question.

Answer: C

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In a certain class, some students donated cans of food to a local food

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