Answer :
To determine the cost of a full tank of gas, we'll break down the steps using the information given in the table.
1. Understand the components:
- The total rental fee includes both the hourly rental cost and the cost of a full tank of gas.
- Our job is to find the cost of the gas.
2. Calculate the hourly rental cost:
- We observe the changes in fees as the hours increase. The differences in fees divided by the differences in hours tell us the cost per hour.
- For example, between 2 and 4 hours, the fee difference is \[tex]$127 - \$[/tex]79 = \[tex]$48. Dividing this by the 2-hour difference, the cost per hour is \$[/tex]48 / 2 = \[tex]$24.
- This calculation remains consistent across other intervals:
- From 4 to 6 hours: \$[/tex]175 - \[tex]$127 = \$[/tex]48, and then \[tex]$48 / 2 = \$[/tex]24.
- From 6 to 8 hours: \[tex]$223 - \$[/tex]175 = \[tex]$48, and then \$[/tex]48 / 2 = \[tex]$24.
- Average hourly cost is therefore \$[/tex]24.
3. Calculate the rental part of the fee (excluding gas):
- Based on the hourly rate, we calculate the fee for just the rental time for various hour intervals:
- For 2 hours: 2 \[tex]$24 = \$[/tex]48
- For 4 hours: 4 \[tex]$24 = \$[/tex]96
- For 6 hours: 6 \[tex]$24 = \$[/tex]144
- For 8 hours: 8 \[tex]$24 = \$[/tex]192
4. Determine the cost of a full tank of gas:
- Subtract the rental part from the total fee to find the cost of gas:
- At 2 hours: \[tex]$79 - \$[/tex]48 = \[tex]$31
- At 4 hours: \$[/tex]127 - \[tex]$96 = \$[/tex]31
- At 6 hours: \[tex]$175 - \$[/tex]144 = \[tex]$31
- At 8 hours: \$[/tex]223 - \[tex]$192 = \$[/tex]31
- We notice that the cost of the gas remains consistently \[tex]$31 across different time intervals.
Thus, the cost for a full tank of gas is \(\$[/tex]31\). Therefore, the correct answer is D. \$31.
1. Understand the components:
- The total rental fee includes both the hourly rental cost and the cost of a full tank of gas.
- Our job is to find the cost of the gas.
2. Calculate the hourly rental cost:
- We observe the changes in fees as the hours increase. The differences in fees divided by the differences in hours tell us the cost per hour.
- For example, between 2 and 4 hours, the fee difference is \[tex]$127 - \$[/tex]79 = \[tex]$48. Dividing this by the 2-hour difference, the cost per hour is \$[/tex]48 / 2 = \[tex]$24.
- This calculation remains consistent across other intervals:
- From 4 to 6 hours: \$[/tex]175 - \[tex]$127 = \$[/tex]48, and then \[tex]$48 / 2 = \$[/tex]24.
- From 6 to 8 hours: \[tex]$223 - \$[/tex]175 = \[tex]$48, and then \$[/tex]48 / 2 = \[tex]$24.
- Average hourly cost is therefore \$[/tex]24.
3. Calculate the rental part of the fee (excluding gas):
- Based on the hourly rate, we calculate the fee for just the rental time for various hour intervals:
- For 2 hours: 2 \[tex]$24 = \$[/tex]48
- For 4 hours: 4 \[tex]$24 = \$[/tex]96
- For 6 hours: 6 \[tex]$24 = \$[/tex]144
- For 8 hours: 8 \[tex]$24 = \$[/tex]192
4. Determine the cost of a full tank of gas:
- Subtract the rental part from the total fee to find the cost of gas:
- At 2 hours: \[tex]$79 - \$[/tex]48 = \[tex]$31
- At 4 hours: \$[/tex]127 - \[tex]$96 = \$[/tex]31
- At 6 hours: \[tex]$175 - \$[/tex]144 = \[tex]$31
- At 8 hours: \$[/tex]223 - \[tex]$192 = \$[/tex]31
- We notice that the cost of the gas remains consistently \[tex]$31 across different time intervals.
Thus, the cost for a full tank of gas is \(\$[/tex]31\). Therefore, the correct answer is D. \$31.
