Question

For meg's long-distance calling plan, mostly cost C in dollars is given by the linear function C (t)= 6 + 0.05t, where t is the number of minutes talked. a) What is the total cost of talking 8 hours? of talking 20 hours? b) What is the effective cost per minute (the total cost divided by the number of minutes talked) of talking 8 hours? of talking 20 hours?

Answer 1

Answer:

It cost $30 to talk for 8 hours and $66 to talk for 20 hours.      

Step-by-step explanation:

We are given the following information in the question:

Cost C in dollars is given by a linear function:

$C(t) = 6 + 0.05t$, where t is the number of minutes talked.

a) Total cost f talking for 8 hours

1 hour = 60 minutes

8 hours = 480 minutes

20 hours = 1200 minutes

Putting t = 480 in the given cost function,

$C(480) = 6 + 0.05\times 480 = 30$

Putting t = 1200 in the given cost function,

$C(1200) = 6 + 0.05\times 1200 = 66$

Thus, it cost $30 to talk for 8 hours and $66 to talk for 20 hours.

b)

$\text{Effective cost per minute} = \displaystyle\frac{\text{Total cost}}{\text{Number of minutes}}$

$\text{Effective cost of talking for 8 hours} = \displaystyle\frac{30}{480} = 0.0625$

$\text{Effective cost of talking for 20 hours} = \displaystyle\frac{66}{1200} = 0.055$

Answer 2

B i think 
Hope it helps