A teacher began grading essays at 4:00 p.m. and completed the task at

Question

A teacher began grading essays at 4:00 p.m. and completed the task at 7:00 p.m. How many essays did he grade?

(1) He took two breaks while grading the essays.
(2) While checking, the teacher averaged 6 essays per hour.

This is a  Data Sufficiency Butler Question

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Adit_ · Answer

This is a similar type of problem to those of A taking a break before reaching his destination and such question almost never give sufficient reasons to answer.

In this case again:
Statement 1:
Just breaks. NOT SUFFICIENT

Statement 2:
Hmm we know the total essays he did IF he were working for 3 hrs continuously. But we know element of taking a break is also a factor. 
Hence NOT SUFFICIENT.

Combining both:
We dont know the DURATION of the break to combine and judge how long he must have worked to know how many essays he completed.
Hence NOT ENOUGH

Answer:  Option E

vasu1104 · Answer

total time = 3 hrs
find= numbers of essays checked 
need rate to determine

s- 1. thats good to know . but we dont know the rate yet. so insufficient.

s-2. now we have rate thats 6 essays per hour. but do we know anything about how she approached those 3 hrs. any breaks? not sufficient

s-1 & 2. now we have rate but we dont know how long those breaks were.

so nothing gets us to the ans.

option E

ExpertsGlobal5 · Answer

Explanation:  
   
The teacher graded essays from 4:00pm to 7:00pm.
  We need to find whether the number of essays graded can be determined.  
 
 Statement (1) 
 
The teacher took two breaks while grading the essays.
 
Since   no information is provided regarding the rate at which essays were graded   it is NOT possible to determine the number of essays graded.   Hence, Statement (1) is insufficient.  
 
 Statement (2) 
 
  While checking  , the teacher averaged 6 essays per hour.
 
Since   no information is provided regarding the amount of time spent grading the essays  , it is NOT possible to determine the number of essays graded.   Hence, Statement (2) is insufficient.  
   
As Statement (1) alone as well as Statement (2) alone is insufficient to answer the question, we need to now combine the two statements. 
 
 Statement (1) and Statement (2) combined  
 
Since the two statements combined give us   no information regarding the amount of time the teacher spent grading the essays  , it is NOT possible to determine the number of essays graded.   Hence, Statement (1) and Statement (2) combined are insufficient.  
 
  E is the correct answer choice.

A teacher began grading essays at 4:00 p.m. and completed the task at

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GMAT Data Sufficiency (DS) Questions

A teacher began grading essays at 4:00 p.m. and completed the task at

Prep Toolkit

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