To determine the correct table that displays the monthly cost of the phone plan based on the number of phone lines, we need to consider the formula for the cost:
Cost = Flat Cost + (Number of Phone Lines × Cost per Line)
The flat cost is $50.00 per month, and the additional fee for each phone line is $20.00. Therefore, the cost can be expressed as:
Cost = $50.00 + ($20.00 × Number of Phone Lines)
Now, let’s calculate the costs for different numbers of phone lines:
- For 0 lines: Cost = $50.00 + ($20.00 × 0) = $50.00
- For 1 line: Cost = $50.00 + ($20.00 × 1) = $50.00 + $20.00 = $70.00
- For 2 lines: Cost = $50.00 + ($20.00 × 2) = $50.00 + $40.00 = $90.00
- For 3 lines: Cost = $50.00 + ($20.00 × 3) = $50.00 + $60.00 = $110.00
- For 4 lines: Cost = $50.00 + ($20.00 × 4) = $50.00 + $80.00 = $130.00
Now, let's compare these results with the provided tables:
-
First Table: | Number of Phone Lines | Cost of the Plan ($) | |----------------------|----------------------| | 0 | 50 | | 1 | 70 | | 2 | 90 | | 3 | 110 | | 4 | 130 |
-
Second Table: | Number of Phone Lines | Cost of the Plan ($) | |----------------------|----------------------| | 0 | 20 | | 1 | 40 | | 2 | 60 | | 3 | 80 | | 4 | 100 |
-
Third Table: | Cost of the Plan ($) | Number of Phone Lines | |----------------------|----------------------| | 20 | 1 | | 40 | 2 | | 60 | 3 | | 80 | 4 | | 100 | 5 |
-
Fourth Table: | Cost of the Plan ($) | Number of Phone Lines | |----------------------|----------------------| | 20 | 0 | | 40 | 1 | | 60 | 2 | | 80 | 3 | | 100 | 4 |
The only table that accurately reflects the calculated values based on the monthly charge for phone lines is the first table.
Therefore, the correct response is the first table:
Number of Phone Lines | Cost of the Plan ($) 0 | 50 1 | 70 2 | 90 3 | 110 4 | 130