Answer: the cost of plan A would be lesser than that of plan B for minutes lesser than 470
Step-by-step explanation:
Let m represent the number of minutes of monthly phone used.
In plan A the customer pays a monthly fee of $25 and then an additional 6 cents per minute of use. It means that the total cost of using m minutes in a month is
0.06m + 25
In plan B the customer pays a monthly fee of $29.70 and then an additional 5 cents per minute of use. It means that the total cost of using m minutes in a month is
0.05m + 29.7
The inequality representing the number of minutes of monthly phone use for which Plan A will cost less than Plan B is
0.06m + 25 < 0.05m + 29.7
0.06m - 0.05m < 29.7 - 25
0.01m < 4.7
m < 4.7/0.01
m < 470
