How many people went on the trip ?

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How many people went on the trip ?

by expert » Sat Apr 11, 2009 1:00 am
Hi guys. Could you please explain how to solve ?
A bus that holds a maximum of 30 people was rented for a trip. How many people went on the trip ?

(1) If fewer than 15 people went on the trip, bus tickets cost $15 per person; if 15 or more people went on the trip, bus tickets cost $12 per person.

(2) The amount of money collected for bus tickets totaled $195.
Official answer is C . I answered E justifying it by the fact that I can't find out exact number of passengers because (1) doesn't have precise condition but rather has more/less language. Apparently I was supposed to divide 195 by 12 and 15 and check what gives integer.

What do you think ?
Source: — Data Sufficiency |

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by Feep » Sat Apr 11, 2009 1:54 am
Yep, it's C.

(1) is clearly insufficient; it merely gives specific pricing information.

(2) is also clearly insufficient; total money without knowing the ticket cost is fairly unless. It could have been $195 for one ticket!

Let's look at the statements together, though. The total is $195, and tickets either cost $15 or $12. But since there are an integer number of people, $12 is impossible: there is no number of people, when multiplied by 12, that will yield $195. So, the ticket price must be instead $15, and some quick division yields 195/15 = 13 people.
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