Question

You are testing an unattended gasoline pump that only accepts credit cards. Once the credit card is validated, the pump nozzle placed into the tank, and the desired grade selected, the customer enters the desired amount of fuel in gallons using the keypad. The keypad only allows the entry of digits. Fuel is sold in tenths (0.1) of a gallon, up to 50.0 gallons.

Which of the following is a minimum set of desired amounts that covers the equivalence partitions for this input?
A. 0.0, 20.0, 60.0
B. 0.0, 0.1, 50.0
C. 0.0, 0.1, 50.0, 70.0
D. -0.1, 0.0, 0.1, 49.9, 50.0, 50.1

Answer 1

The minimum set of desired gasoline amounts that covers the equivalence partitions is Option B: 0.0, 0.1, 50.0. These selections represent the lower boundary, an interior point, and the upper boundary of valid input for the gasoline pump.

Step-by-step explanation:

The question pertains to determining the minimum set of desired amounts of gasoline to test an unattended pump that allows entry in tenths of a gallon up to 50.0 gallons. Equivalence partitioning is a software testing technique where input data is divided into partitions of equivalent data from which test cases can be derived. In this case, the partitions are: below the minimum valid input, minimum valid input, valid input range, and above the maximum valid input.

Considering the valid input range is from 0.1 to 50.0 gallons, we would take:

• The lowest valid value, just above the invalid entry - 0.1
• A value well within the valid range - 20.0
• The upper boundary of the valid range - 50.0

Invalid entries are not required as part of equivalence partitioning when determining the minimum set. Therefore, the best answer from the provided options is B. 0.0, 0.1, 50.0, which covers the lower boundary, an interior point, and the upper boundary of valid input for the system.