Question

When you buy an item on which sales tax is charged,the total cost is calculated by the formula T=P+s/100p where T is the total cost,p is the items price,and s is the sales tax rate (as a percent). If you pay $14.77 for an item priced at $14, what was the tax rate ?

Answer 1

Given:

The formula for total cost is

$T=p+\dfrac{s}{100}p$

where, p is the price of item and s is the sales tax rate (as a percent).

You pay $14.77 for an item priced at $14.

To find:

The the tax rate.

Solution:

You pay $14.77 for an item priced at $14. So,

Total cost (T) = $14.77

Price of item (p) = $14

Putting T=14.77 and p=14 in given formula, we get

$14.77=14+\dfrac{s}{100}(14)$

$14.77-14=\dfrac{s}{100}(14)$

$0.77=\dfrac{s}{100}(14)$

Multiply both sides by 100.

$77=14s$

Divide both sides by 14.

$\dfrac{77}{14}=s$

$5.5=s$

Therefore, the tax rate is 5.5%.