Answer:
After 59 months the new dryer will pay for itself.
Step-by-step explanation:
Let the new clothes dryer takes 'x' months to pay for itself.
Then the operating cost of the new dryer will be = 15x
Since cost of the new dryer = $590
So, total cost of the dryer in x months = $(590 + 15x)
Now we know old dryer's operating cost is = $25 per month
So, operating cost for x months = 25x
By the time when new dryer's total cost becomes equal to the old dryer's operational cost, the new dryer will pay for itself.
Now we can get the value of x by equating the old dryer's operational cost and the new dryer's total cost.
25x = 590 + 15x
25x - 15x = 590
10x = 590
x =
x = '59 months'