To determine Rob's total monthly utility and maintenance expenses, we need to calculate costs for each utility and then sum them up along with the maintenance costs.
1. Electricity Cost Calculation:
- Rob uses 215 kWh of electricity.
- The rate for electricity is [tex]$0.15 per kWh.
- Electricity cost: \( 215 \, \text{kWh} \times 0.15 \, \text{\$[/tex]/kWh} = 32.25 \, \text{\[tex]$} \).
2. Gas Cost Calculation:
- Rob uses 900 cubic feet (ft³) of gas.
- The rate for gas is $[/tex]1 per 100 ft³.
- Gas cost: [tex]\( \frac{900 \, \text{ft}^3}{100} \times 1 \, \text{\$/100 ft}^3 = 9.00 \, \text{\$} \)[/tex].
3. Water Cost Calculation:
- Rob uses 450 gallons of water.
- The rate for water is [tex]$0.03 per 10 gallons.
- Water cost: \( \frac{450 \, \text{gal}}{10} \times 0.03 \, \text{\$[/tex]/10 gal} = 1.35 \, \text{\[tex]$} \).
4. Phone and Internet Costs:
- Phone cost per month: \( 40 \, \text{\$[/tex]} \).
- Internet cost per month: [tex]\( 100 \, \text{\$} \)[/tex].
5. Total Utility Cost Calculation:
- Add the costs for electricity, gas, water, phone, and internet.
- Total utility cost: [tex]\( 32.25 \, \text{\$} + 9.00 \, \text{\$} + 1.35 \, \text{\$} + 40 \, \text{\$} + 100 \, \text{\$} = 182.60 \, \text{\$} \)[/tex].
6. Total Monthly Expense Calculation:
- Add the total utility cost to the maintenance cost.
- Maintenance cost per month: [tex]\( 120 \, \text{\$} \)[/tex].
- Total monthly expense: [tex]\( 182.60 \, \text{\$} + 120 \, \text{\$} = 302.60 \, \text{\$} \)[/tex].
Therefore, Rob's total monthly utility and maintenance expenses are \$302.60.
