Question

A regular tube of toothpaste costs $2.50 for 3.2 ounces. A travel size tube costs $1.00 for 1.2 ounces. Compare the prices and weights using percent to decide which is better to buy

Answer 1

Answer:

The travel size costs 6 ​% as much as the regular size. Thus the regular size would be more economical and thus a better buy

Step-by-step explanation:

step 1

Find out the unit rate of a regular  tube of toothpaste

we know that

To find out the unit rate, divide the total cost by the total weight

so

$\frac{2.50}{3.2}=\ 0.78\ per\ ounce$

step 2

Find out the unit rate of a travel size tube of toothpaste

we know that

To find out the unit rate, divide the total cost by the total weight

so

$\frac{1.00}{1.2}=\ 0.83\ per\ ounce$

step 3

Find out the percent of increase

we have that

The unit rate $\ 0.83\ per\ ounce$ represent the 100%

so by proportion

Find out what percentage represent the difference ($0.83-$0.78=$0.05 per ounce)

$\frac{0.83}{100\%}=\frac{0.05}{x}\\\\x=100(0.05)/0.83\\\\x=6\%$

therefore

The travel size costs 6 ​% as much as the regular size. Thus the regular size would be more economical and thus a better buy