Answer: 200 minutes have to be used for the costs of both plans to be the same.
Step-by-step explanation:
Let x represent the number of minutes that have to be used for the costs of both plans to be the same.
Package A is $35.00 per month with an additional charge of $0.15 per minute for long distance. This means that the cost of using package A for x minutes in a month would be
35 + 0.15x
Package B is $45.00 per month with an additional charge of $0.10 per minute for long distance. This means that the cost of using package A for x minutes in a month would be
45 + 0.1x
For both costs to be the same, it means that
35 + 0.15x = 45 + 0.1x
0.15x - 0.1x = 45 - 35
0.05x = 10
x = 10/0.05
x = 200
