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

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

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

`(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

`(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)

`(0.83)/(100\%)=(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