Open Ended Algebra 2. Please help?

[erica]

In a class that gives little help with almost no explanation. If you don't mind, I could use some help:


Paul manages Mr. Aldo's Dog Grooming Salon. Always being cost conscious, Mr. Aldo instructs Paul to find out if buying shampoo on a yearly basis saves money. Paul finds out that it will cost him $1.87 per quart or $7.99 per gallon. There are five employees who each average giving 13 shampoos a day. It takes three fluid ounces per wash and the shop is open an average of 6 days a week.


In which quantity should he purchase the shampoo in order to keep Mr. Aldo happy? What is the difference of the costs to the nearest dollar?

**work below

 

[erica]

sorry.
i havent gotten far. i first wrote down all the numerical values within the problem.

$1.87 per quart, $7.99 per gallon

13 shampoos per day = 3 ounces each

13 * 3 =39 ounces a day

39 ounces * 6 days a week =234 ounces per week

$1.87 * 4 quarts = $7.48 (= one gallon)

1 gallon = 128 ounces

234 / 128 = 1.83 gallons used per week

And now I am stuck. I shared this work with my teacher and she didn't help at all, but did say it wasn't finished or correct.

$7.48 (quarts)

 

[erica]

i've continued working...
4 quarts = 1 gallon
4 quarts = 32 ounces
1 gallon = 234
$1.87 * 4 = $7.48
234 ounces per week / 128 ounces per gallon = 1.83 gallons
52 weeks = 1 year
234 ounces per week * 52 weeks = 12168 ounces used per year
12168 ounces per year / 32 ounces per quart = about 380 quarts used per year
12168 ounces per year / 128 ounces per gallon = about 95 gallons used per year
$1.87 * 380 = $710.60
$7.99 * 95 = $759.05.

Am i done?