Question

A quarterly telephone bill consist of N$79.15 rental plus 4.7 cents for each dialled unit. Sales tax is added at 15%. What is the total bill for Mrs. Jones who used 915 dialled units?

Answer 1

$4.7 × 915 = 4300.5
$4300.5 + 79.15 = 4379.65
15% of 4379.65 = 656.9475
4379.65 + 656.9745 = 5036.6245
Mrs. Jones' Bill was $5036.63
(Rounded to the nearest 1/10)

Answer 2

$140.48

Explanation:

Let x represent dialed units.

We have been given that a quarterly telephone bill consist of $79.15 rental plus 4.7 cents for each dialed unit.

4.7 cents = $0.047

Cost of dialing x units would be
`0.047x`.

Total cost of dialing x units would be
`0.047x+79.15`.

Let us find cost of dialing 915 units by substituting
`x=915` in above expression.

`0.047(915)+79.15`

`43.005+79.15`

`122.155`

Now, we will find 15% of sales tax as:

`122.155* (15)/(100)`

`122.155* 0.15`

`18.32325`

Total bill:
`18.32325+122.155=140.47825\approx 140.48`

Therefore, Mrs. Jonas's bill would be $140.48.