A helicopter company charges $85 for the first kilometer...

[BTGmoderatorLU]

A helicopter company charges $85 for the first kilometer of a trip and $5 every kilometer after that. If the total cost of a trip was $365, how many kilometers were flown?

A. 55
B. 56
C. 57
D. 58
E. 59

The OA is C.

Experts, can I say that the total cost will be determined by the formula, T = 85+5k ( where k represent the additional kilometers after the first kilometer of the trip)?

Then, 365 = 85 + 5k, the value of k will be, k = (365 - 85) / 5 = 56 kilometers, that's mean that the total kilometers of the trip was 57. Right?

Experts, any suggestion about this PS question? Thanks in advance.

[Brent@GMATPrepNow]

A helicopter company charges $85 for the first kilometer of a trip and $5 every kilometer after that. If the total cost of a trip was $365, how many kilometers were flown?

A. 55
B. 56
C. 57
D. 58
E. 59

The OA is C.

Experts, can I say that the total cost will be determined by the formula, T = 85+5k ( where k represent the additional kilometers after the first kilometer of the trip)?

Then, 365 = 85 + 5k, the value of k will be, k = (365 - 85) / 5 = 56 kilometers, that's mean that the total kilometers of the trip was 57. Right?

Experts, any suggestion about this PS question? Thanks in advance.

Perfect approach!

Cheers,
Brent

[Scott@TargetTestPrep]

A helicopter company charges $85 for the first kilometer of a trip and $5 every kilometer after that. If the total cost of a trip was $365, how many kilometers were flown?

A. 55
B. 56
C. 57
D. 58
E. 59

The OA is C.

For a trip of x miles, we pay $85 for the first kilometer and $5 for each of the remaining (x - 1) kilometers. We can create the following equation for the cost of the trip

85 + 5(x - 1) = 365

5x - 5 = 280

5x = 285

x = 57

Answer: C