Fractions. please help!

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Fractions. please help!

by tsmith93 » Wed Mar 03, 2010 6:39 pm
A number of people boarded a bus at the terminal. At the first stop, half of the passengers got off and 1 got on. At the second stop, 1/3 of the passengers on the bus got off and 1 got on. If the bus then had 15 passengers, how many were there when the bus left the terminal?

(A) 40
(B) 48
(C) 58
(D) 60
(E) 62
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by truplayer256 » Wed Mar 03, 2010 8:22 pm
Let the number of people who boarded the bus at the terminal be represented by the variable x.

At the first stop, the number of passengers remaining will be: x/2 + 1

At the second stop, the number of passengers remaining will be:2/3(x/2 + 1)+1

2/3(x/2 + 1) + 1=15

x=40

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by kstv » Thu Mar 04, 2010 1:15 am
A number of people boarded a bus at the terminal. At the first stop, half of the passengers got off and 1 got on. At the second stop, 1/3 of the passengers on the bus got off and 1 got on. If the bus then had 15 passengers, how many were there when the bus left the terminal?

A good example in which to back calculate that
Bus had 15 passenger after the second stop. 1 passenger boarded the bus. Before that it was 15-1 = 14.
14 was after 1/3 got down . Before it there were = 14 X 2/3 = 21
Repeat for 1st stop. 21 - 1 = 20 . 1/2 = 20.
At the terminal there were 20X2 = 40

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by sanju09 » Thu Mar 04, 2010 3:44 am
tsmith93 wrote:A number of people boarded a bus at the terminal. At the first stop, half of the passengers got off and 1 got on. At the second stop, 1/3 of the passengers on the bus got off and 1 got on. If the bus then had 15 passengers, how many were there when the bus left the terminal?

(A) 40
(B) 48
(C) 58
(D) 60
(E) 62
Just 2 steps

Step 1

Ask yourself that 1 more than half of which of the following is a multiple of 3; and eliminate B, D, and E.

Step 2

Now ask 1 more than 2/3 of which of 21 and 30 is 15 and win 21.


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