To determine the total cost of a 31-minute international phone call, let's break down the pricing structure and calculate the cost step-by-step:
1. Cost for the First Minute:
The cost for the first minute of the phone call is fixed at 15 cents.
2. Cost for Additional Minutes:
For each additional minute beyond the first minute, the cost is 3 cents per minute. Since the first minute is already accounted for separately, we need to calculate the cost for the remaining 30 minutes (31 total minutes - 1 minute).
3. Calculate the Cost for Additional Minutes:
To find the cost for the additional 30 minutes, multiply the number of additional minutes by the cost per additional minute:
\(\[
\text{Additional Minutes} = 31 - 1 = 30 \text{ minutes}
\]\)
\(\[
\text{Cost for Additional Minutes} = 30 \text{ minutes} \times 3 \text{ cents} = 90 \text{ cents}
\]\)
4. Total Cost of the Call:
Finally, add the cost of the first minute to the cost of the additional minutes to get the total cost of the phone call:
\(\[
\text{Total Cost} = \text{Cost of First Minute} + \text{Cost of Additional Minutes}
\]\)
\(\[
\text{Total Cost} = 15 \text{ cents} + 90 \text{ cents} = 105 \text{ cents}
\]\)
Therefore, the total cost of a 31-minute international phone call is 105 cents.
