You are choosing between two​ long-distance telephone plans. Plan A has a monthly fee of ​$25.00 with a charge of ​$0.05 per minute for all​ long-distance calls. Plan B has a monthly fee of ​$15.00 with a charge of ​$0.15 per minute for all​ long-distance calls. Complete parts a and b.

a. For how many minutes of​ long-distance calls will the costs for the two plans be the​ same?

To find the number of minutes where the costs for the two plans are the same, we need to set up an equation.

For Plan A, the cost is $25 + $0.05 per minute.
For Plan B, the cost is $15 + $0.15 per minute.

Let's set these two expressions equal to each other and solve for the number of minutes (m) when the costs are the same:

$25 + $0.05m = $15 + $0.15m

Subtracting $0.05m from both sides gives:

$10 = $0.1m

Dividing both sides by $0.1 gives:

m = $10 / $0.1 = 100

Therefore, for 100 minutes of long-distance calls, the costs for Plan A and Plan B will be the same.

b. Which plan is better if you expect to use less than 100 ​minutes?

What will be the cost for each​ plan?

To determine the cost for each plan, we need to calculate the total cost based on the number of minutes of long-distance calls.

For Plan A, the cost is $25.00 plus $0.05 per minute.
For Plan B, the cost is $15.00 plus $0.15 per minute.

Let's calculate the costs for each plan for various numbers of minutes:

For Plan A:
1. 10 minutes: $25.00 + ($0.05 * 10) = $25.00 + $0.50 = $25.50
2. 50 minutes: $25.00 + ($0.05 * 50) = $25.00 + $2.50 = $27.50
3. 100 minutes: $25.00 + ($0.05 * 100) = $25.00 + $5.00 = $30.00
4. 150 minutes: $25.00 + ($0.05 * 150) = $25.00 + $7.50 = $32.50

For Plan B:
1. 10 minutes: $15.00 + ($0.15 * 10) = $15.00 + $1.50 = $16.50
2. 50 minutes: $15.00 + ($0.15 * 50) = $15.00 + $7.50 = $22.50
3. 100 minutes: $15.00 + ($0.15 * 100) = $15.00 + $15.00 = $30.00
4. 150 minutes: $15.00 + ($0.15 * 150) = $15.00 + $22.50 = $37.50

Therefore, the cost for each plan for various numbers of minutes would be as follows:

Plan A:
- 10 minutes: $25.50
- 50 minutes: $27.50
- 100 minutes: $30.00
- 150 minutes: $32.50

Plan B:
- 10 minutes: $16.50
- 50 minutes: $22.50
- 100 minutes: $30.00
- 150 minutes: $37.50

In this comparison, Plan B is better if you expect to use less than 100 minutes as it has a lower base monthly fee ($15.00) compared to Plan A ($25.00). However, for usage exceeding 100 minutes, Plan A becomes more cost-effective.