Pete works at three part-time jobs to make extra money. What are hisav

Question

Pete works at three part-time jobs to make extra money. What are hisaverage earnings per hour?

(1) Pete earned $500 for 20 hours at the first job, $150 for 10 hours at the second job, and $100 for 5 hours at the third job.

(2) Pete earned an average of $25 per hour at the first job, $15 per hour at the second job, and $20 per hour at the third job.

AlexEvsyukov · Answer

The answer is D. 
If we look at (2), it is easy to get average salary for Pete: (25+15+20)/3= 20 - sufficient. 
(1) basically gives as the same result if we divide money earned by a number of hours - sufficient.

huongguyen · Answer

Pete works at three part-time jobs to make extra money. What are his average earnings per hour?

(1) Pete earned $500 for 20 hours at the first job, $150 for 10 hours at the second job, and $100 for 5 hours at the third job.
=> average per hour = (500 + 150 + 100) / (20 + 10 + 5)
=> sufficient

(2) Pete earned an average of $25 per hour at the first job, $15 per hour at the second job, and $20 per hour at the third job.

=> average per hour = (25 + 15 + 20) / (1 + 1 + 1)
=> sufficient

IMO:   D

sanjitscorps18 · Answer

IMHO the answer is Option A

1. Pete earned $500 for 20 hours at the first job, $150 for 10 hours at the second job, and $100 for 5 hours at the third job.
Average Payment / hour = Total Payment / Total hours worked
= ($500 + $150 + $100) / (20 + 10 + 5) hours
Hence sufficient

2. Here we are given average payment/hour worked at each job but we have no information about the number of hours worked at each job
Average Payment / hour = Total Payment / Total hours worked
Average Payment / hour = Average Hour-rate x  hours worked  / Total hours worked

E.g. if Pete worked 2 hours for Job 1, then 10 hours for job 2 and then 30 hours for job 3 the Average Payment/hour would be 
(25 x 2 + 15 x 10 + 20 x 30)/(2+10+30) and that is approximately $19/hr
The equation (25 + 15 + 20) / (1 + 1 + 1) works only if he works 1 hour per job where the hourly average is $20/hr
Hence insufficient

abdiy2 · Answer

Seems to me like its not stated how many hours he actually works at each job, so we cannot weight them. I'm not sure that saying 'he earned 500 for 20 hours' and '150 for 10 hours', is the same as saying he worked twice as much of the first as the second, right?

So I think D

So I think  D

sanjitscorps18 · Answer

D would mean that both answers are correct independently and that is not the case.

However, the hours in this question is the weight as it determines the overall average. Also we are not comparing a specific amount of work. We are only considering hours spent and the amount earned. Hence only option A gives complete information.

Hope this helps!

Posted from my mobile device

dadie · Answer

Answers is A

1 - We can compute his average work per hour...
2 Even we have the average of each work, we don't know the weight of each work in Pete's revenue.

Bunuel · Answer

This question is a part of  Are You Up For the Challenge: 700 Level Questions  collection.

Advait01 · Answer

Since B says average, we cannot accurately determine the actual number of hours he worked at each job
Hence A

Pete works at three part-time jobs to make extra money. What are hisav

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Pete works at three part-time jobs to make extra money. What are hisav

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