The function f(x) = 0.11x + 43 relates how much Derek pays for phone service, f(x), to the number of minutes, x, used for intern
ational calls in a month. What is the value and meaning of f(320)? A. $78.20; this is the amount Derek pays for 320 months of service $78.20; / B.this is the amount Derek pays for 320 minutes of international calls $92.50; / C.this is the amount Derek pays for 320 months of service $92.50; / D. this is the amount Derek pays for 320 minutes of international calls
Given the function f(x) = 0.11x + 43, this shows the relationship between how much Derek has to pay for phone service for the amount of minutes he uses on international calls a month.
f(320) can be solved by substituting x = 320, and this is shown below:
$7.10 per hour needs to be times by 24 (to calculate the pay per day) = $170.40 then times that by 9 = $1533.60 (The pay for 9 days which is coincidently the pay per 2 weeks!