A prepaid phone card has a balance of $22.40 remaining. If calls are $0.035 per minute, which equation represents the number of minutes, m, you may talk using the card?

Question

asked Mar 17, 2021 37.6k views

1 Answer

Erika · Answer 1 · 2021-03-23T14:29:49+0000

Answer:

The equation that represents the number of minutes that Imay talk using the card is
$m =28.571\cdot C$ .

Explanation:

From statement we know that balance (
), measured in US dollars, is directly proportional to remaining call time (
), measured in minutes. That is:

$C \propto m$

$C = k\cdot m$ (Eq. 1)

Where
is the proportionality ratio, measured in US dollars per minute.

If we know that
$k = 0.035\,(USD)/(min)$ , then the equation is:

$C = 0.035\cdot m$

Now we clear remaining call time within equation:

$m =28.571\cdot C$

The equation that represents the number of minutes that Imay talk using the card is
$m =28.571\cdot C$ .