Dealership

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Dealership

by MBA.Aspirant » Sun Oct 23, 2011 8:29 am
A certain dealership has a total of 100 vehicles consisting of cars and trucks. If 1/2 of the cars are used, and 1/3 of the trucks are used. If there are 42 used cars altogether, how many trucks are there?

A) 32
B) 36
C) 40
D) 45
E) 48


The OA explanation does it by POE and checking sum. I was wondering how to solve it algebraically.

Thanks
Source: — Problem Solving |

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by MBA.Aspirant » Sun Oct 23, 2011 10:07 am
Got it, thanks!

c+t = 100

c= 100 - t

1/2 c + 1/3 t = 42

50 - 1/2 t + 1/3 t = 42

1/3 t - 1/2 t = -8

1/6 t = 8

t = 48

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by neelgandham » Sun Oct 23, 2011 12:50 pm
Say the # of Cars = C
Say the # of Trucks = T

Then C + T = 100
and 0.5C + 0.33 T = 42

Solving the equations we get the value of T !
Anil Gandham
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