Question

Let f(a) = a/12.99, g(a) = |_a/12.99_| and h(a) = .082a-.365

Evaluate f(151)

Evaluate g(87)

Evaluate h(317)

An airlines provides Airfone service for passengers to make calls from the air. Below is a graph of the cost of making a call for various durations. Airfone Costs CA 12 11 10 9 8 7 0 1 2 3 4 Length of Call (minutes) 5 6 7 L How much would a 9.2 minute phone call cost? Answer: Cost (dollars)

Express the cost C(in dollars) as a function of the duration L(in minutes) of a call.

Answer 1

Question 1:

f(151) = 151/12.99 = 11.62

g(87) = floor(151/12.99) = 11

h(317) = 0.082(317) - 0.365 = 25.629

Question 2:

The initial cost of phone call in the range of 0-1 minutes is equal to 5.5$

For each every 1 minute, the cost increase by factor of 3$

Hence, the charge for 9.2 minute phone call = 5.5 + 9 * 3 = 5.5 + 27 = 32.5$

Hence the cost of 9.2 minutes pone call cost will be equal to 32.5$

The function can be written as

C(L) = 5.5, 0<L<=1

5.5 + 3*Ceil|L-1|, L>1

Note - Post any doubts/queries in comments section.