Understanding Cell Phone Billing

The video tutorial explains how a cell phone company charges a monthly fee plus a per-minute rate. It guides viewers through setting up a graph with talk time on the horizontal axis and cost on the vertical axis. The tutorial covers creating ordered pairs, forming a table, and plotting these on a graph. It also explains how to write and verify an equation representing the relationship between talk time and cost. Finally, it discusses how the cost changes with increased talk time.

What is the fixed monthly charge for the cell phone service?

• $15

• $8

• $5

• $10

How much does the company charge per minute of talk time?

• 10 cents

• 20 cents

• 25 cents

• 15 cents

In the context of the graph, what is the input quantity?

• Data usage

• Number of calls

• Cost in dollars

• Talk time in minutes

What is the output quantity in the graph?

• Data usage

• Talk time in minutes

• Number of calls

• Cost in dollars

What is the ordered pair for 10 minutes of talk time?

• (10, 11)

• (10, 12.5)

• (10, 9.5)

• (10, 8)

What pattern is observed in the ordered pair table as talk time increases by 10 minutes?

• Cost increases by $1

• Cost increases by $1.5

• Cost increases by $2.5

• Cost increases by $2

What does the ordered pair (20, 11) represent?

• 20 minutes of talk time costs $12.5

• 20 minutes of talk time costs $9.5

• 20 minutes of talk time costs $8

• 20 minutes of talk time costs $11

What is the equation representing the total cost C in terms of minutes M?

• C = 10 + 0.20M

• C = 8 + 0.10M

• C = 10 + 0.15M

• C = 8 + 0.15M

How much does the cost increase for every additional minute talked?

• 20 cents

• 15 cents

• 10 cents

• 25 cents

If the talk time is 80 minutes, what is the total cost?

• $18.5

• $20

• $21.5

• $23