Problem Solving

rtaha2412 wrote:A computer programmer needs to print 148 documents. The documents have an average length of 10 pages and the printer takes 15 seconds to print each page. Approximately how many hours will it take to print all the documents if they are printed without interruptions?
a 1/2 hr
b 2 hr
c 2 1/2 hr
d 6 hr
e 24 hr

Total number of pages = 148 documents X 10 pages per document = 1480 pages
Time required to print the documents = 1480 pages X 15 seconds to print each page = 1480*15 seconds

1480*15 seconds = (1480*15)/(60*60) hours = 6 hours (Approximately)

The correct answer is D.

rtaha2412 wrote:thank you all. i know see that you have to multiply 1480*15/3600 but i do not understand why the time is 6 hrs. what is the full work/rate equation so i can see how many documents get printed in the 6 hrs

Full work = Pages to be printed = 148 documents X 10 per document = 1480 pages
Rate = 1 page is printed in 15 seconds = 1/15 pages per second = (1/15)*60 pages per minute = 4 pages per minute = 4*60 pages per hour = 240 pages per hour

Therefore, total time required = Full work/Rate = 1480/240 hour = 6.167 hours = approximately 6 hours.

Hope it is clear now.

rtaha2412 wrote:Thanks for the help

A computer programmer needs to print 148 documents. The documents have an average length of 10 pages and the printer takes 15 seconds to print each page. Approximately how many hours will it take to print all the documents if they are printed without interruptions?
a 1/2 hr
b 2 hr
c 2 1/2 hr
d 6 hr
e 24 hr

It will take (148 x 10) x 15 = 1480 x 15 seconds to complete printing all the documents. We convert seconds to hours (3600 seconds in one hour), obtaining:

(1480 x 15)/3600 = (148 x 15)/360 = 148/24 ≈ 6 hours.

Answer: D

Hi All,

We're told that a computer programmer needs to print 148 documents, each document has an average length of 10 pages and the printer takes 15 seconds to print each page. We're asked for the approximate number of hours needed to print all the documents if they are printed without interruptions. While this is an older question, it's a nice example of how the math can be approached in a number of different ways - and there's a way to use estimation (and the 'spread' of the Answer choices) to avoid a lot of heavy Arithmetic.

Since the documents have an average length of 10 pages and each page takes 15 seconds to print, the average time to print each document would be 150 seconds = 2.5 minutes. If we estimate 150 documents at 2 minutes each, then that would be 300 minutes = 5 hours. There's only one answer that's close to that estimate....

Final Answer: D

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