Three friends rented a car for a week and divided the cost equally. If

Question

Three friends rented a car for a week and divided the cost equally. If a fourth friend had joined them and the cost had been divided equally among the 4 friends, then the cost to each of the original 3 friends would have been reduced by $15? What was the total cost of renting the car?

a) $60
b) $100
c) $140
d) $160
e) $180

(A) $60
(B) $100
(C) $140
(D) $160
(E) $180

PS07318

attari92 · Answer

Let the initial cost for each of the three friends be x units.
Total cost =3x units
Now, a new guy came in then the cost per friend =3x/4 units
reduction in cost =x-3x/4=x/4 ; And x/4 =15 =>x=60 
total cost =3*60=180 =>E

Princ · Answer

OA: E

Total cost of trip : x
as per question stem
 \frac{x}{3}-\frac{x}{4}=15 
 \frac{x}{12}=15 
 x=12*15=180

BrentGMATPrepNow · Answer

Let's start with a word equation: ( cost per person with 4 friends ) = ( cost per person with 3 friends ) - $15

Let T = the total cost of renting the car

So,  cost per person with 4 friends = T/4 
And  cost per person with 3 friends = T/3

We can now take our word equation and fill in the missing parts to get:  T/4  =  T/3  - 15
To eliminate the fractions, multiply both sides by 12 to get: (12 T/4 ) = 12( T/3  - 15)
Expand: 3T = 4T - 180
Solve: T = 180

Answer: E

Cheers,
Brent

gmatns2018 · Answer

2step question 
cost for 4th firend --> 15*3 -- 45
total cost 45 * 4 -- 180

ScottTargetTestPrep · Answer

We can let the cost of the rental = n and create the equation:

n/3 = n/4 + 15

Multiplying by 12, we have:

4n = 3n + 180

n = 180

Answer: E

GPN123 · Answer

Check for the answer choices.

Our best bet would be that the cost is divisible by both 3 and 4.

Out of all the options, only 60 and 180 is divisible by both.

Check one of them. I checked 180, cause 60 seemed too less to give a difference of 15.

Solved in less than 20 secs :D

Posted from my mobile device

mimajit · Answer

This is how i solved

Let the initial cost for each of the three friends be x units.
Total cost =3x units
Now, a new guy came in then the cost per friend =x-15 
Therfore (X-15) *4 =3x
or 4x -60 =3x
x= 60 ( This is share per person of the original 3 friends )

Cost = 3X or 3* 60 = 180 or E

total cost =3*60=180 =>E

daffy8 · Answer

Since the values are integers and there are 2 averages mentioned in the question with 3 people and 4 people therefore the total should be a multiple of 3 and 4. Only 180 suffices among all the answer choices listed.

Rwoot · Answer

Let a be the average cost among three friends
as per question 
a-15=3a/4
simplifying we get a -> 60
total cost a*3 -> 180

bumpbot · Answer

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Three friends rented a car for a week and divided the cost equally. If

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Three friends rented a car for a week and divided the cost equally. If

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