A restaurant bill comes to $28.35. How do you find the total cost if the tax is 6.25% and a 20% tip is left on the amount before tax?

1 Answer
Aug 15, 2017

See a solution process below:

Explanation:

First, we can determine the amount of the tax:

#t = b * r#

Where:

#t# is the amount of the tax.

#b# is the amount of the bill - $28.35 for this problem.

#r# is the tax rate. #6.25%# for this problem. Percent or % means per 100 or out of 100. We can write #6.25%# as #6.25/100#

Substituting gives:

#t = $28.35 * 6.25/100#

#t = ($177.1875)/100#

#t = $1.771875#

#t = $1.77#

Next, we can determine the amount of the tip:

#p = b * g#

Where:

#p# is the amount of the tip.

#b# is the amount of the bill - $28.35 for this problem.

#g# is the gratuity rate. #20%# for this problem. Percent or % means per 100 or out of 100. We can write #20%# as #20/100#

Substituting gives:

#p = $28.35 * 20/100#

#p = ($567.00)/100#

#p = $5.67#

Now, we can add the amount of the bill, the tax and tip amounts to find the total cost:

#$28.35 + $1.77 + $5.67 = $35.79#