The charge for a telephone call between City R and City S is $0.42 for each of the first 3 minutes and $0.18 for...

[BTGmoderatorLU]

Source: GMAT Paper Tests

The charge for a telephone call between City R and City S is $0.42 for each of the first 3 minutes and $0.18 for each additional minute. A certain call between these two cities lasted for x minutes, where x is an integer. Hoa many minutes long was the call?

1) The charge for the 3 minutes of the call was $0.36 less than the charge for the remainder of the call.
2) The total charge for the call was $2.88.

The OA is D

[swerve]

Source: GMAT Paper Tests

The charge for a telephone call between City R and City S is $0.42 for each of the first 3 minutes and $0.18 for each additional minute. A certain call between these two cities lasted for x minutes, where x is an integer. Hoa many minutes long was the call?

1) The charge for the 3 minutes of the call was $0.36 less than the charge for the remainder of the call.
2) The total charge for the call was $2.88.

The OA is D

1) The charge for the first 3 minutes of the call was $0.36 less than the charge for the remainder of the call.
\(3\cdot 0.42=0.18\cdot y - 0.36\) (\(y\) is the number of minute for the remainder call) we can find the value of y and then y+3 ( the first minutes called). Sufficient \(\Large{\color{green}\checkmark}\)

2) The total charge for the call was $2.88
\(3\cdot 0.42+0.18\cdot z=2.88\) we also can find \(z\) and \(z+3=\) the number of minutes the call last. Sufficient \(\Large{\color{green}\checkmark}\)

Hence, D