Answer:

Explanation:
Current plan : customers are charged a flat rate of $175 per month.
The new plan would charge a flat rate of $94 plus an additional $4.50 per device connected to the network.
Let the number of devices be x
Charge of 1 device = $4.50
Cost of x devices = $4.5x
So, total charge of new plan = 94+4.5x
Now we are given that the number of devices, x, for which the cost of the new plan is less than the current plan.





Thus no. of devices cannot be more than of equal to 18 .
Refer the attached graph.