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by chacha0212 » Thu Dec 04, 2014 12:04 pm
Last year, a public transportation system sold an average (arithmetic mean) of 41,000 tickets per day on weekdays (Monday through Friday) and a average of 18, 000 tickets per day on Saturday and Sunday. Which of the following is closest to the total number of tickets sold last year?

A) 1 mil
B) 1.25 mil
C) 10 mil
D) 12.5 mil
E) 125 mil

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by [email protected] » Thu Dec 04, 2014 12:16 pm
Hi chacha0212,

Since the answer choices are relatively "spread out", we can use estimation on this question (as an additional "clue", the phrase "closest to the total..." in the prompt also leads me to believe that estimation will be a good option).

We're told that....
An average of 41,000 tickets per day Monday - Friday
An average of 18,000 tickets per day Saturday and Sunday

....are sold. We're asked for the value that is closest to the total number of tickets sold for a YEAR.

First, let's figure out the number of tickets sold in 1 WEEK:

(41,000)(5) + (18,000)(2) =
205,000 + 36,000 =
241,000 tickets per week

Since we're estimating, we'll say a year is 52 weeks. Thus, we have...

(241,000)(52)

Using rounding, we'll call this....

(240,000)(50) = 12,000,000

Since we rounded both values "down", we know the correct answer will be a little bigger than 12 million.

Final Answer: D

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Rich
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by Brent@GMATPrepNow » Thu Dec 04, 2014 12:16 pm
chacha0212 wrote:Last year, a public transportation system sold an average (arithmetic mean) of 41,000 tickets per day on weekdays (Monday through Friday) and a average of 18, 000 tickets per day on Saturday and Sunday. Which of the following is closest to the total number of tickets sold last year?

A) 1 mil
B) 1.25 mil
C) 10 mil
D) 12.5 mil
E) 125 mil
The word "closest" suggests that we can use some estimation here.

Let's first estimate the number of tickets sold PER WEEK
41,000 tickets per day on weekdays
(5)(41,000) = 205,000

18,000 tickets per day on weekends
(2)(18,000) = 36,000

So, total tickets sold PER WEEK = 205,000 + 36,000 = 241,000
To make our calculations easier, let's round it off to 240,000 tickets per week

There are 52 weeks in the years, so the TOTAL (annual) ticket sales is (52)(240,000)
HOWEVER, since the GMAT is not testing whether or not you are a human calculator, we can probably just say there are 50 weeks in a year.

(50)(240,000) = 12,000,000
Of course, there are actually 52 weeks in the year, so the correct answer is a BIT MORE than 12,000,000

Choose D

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
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