Question

A boutique sold $127.50 worth of purses for $7.50 each.=. How many purses did they sell?

Answer 1

`($127.50)/($7.50)=17`

Explanation:

Check: `17xx$7.50=$127.50`

Answer 2

The same as Meneerr but with a slight twist (underlying principle)

17 purses were sold

`color(red)("I am sure I have seen this question before!")`

Explanation:

Using ratio

`("total cost")/("single cost")->("total count")/("single count =1")`

`=>127.5/7.5 -=("total count")/1`

Need to change the denominator of 7.5 to the value of 1 but maintain the ratio. What you do to the bottom you do to the top (for multiply or divide).

'....................................................................................................................
`color(brown)("The next line is where Meneerr's shortcut method comes in")`

`=>(127.5-:7.5)/(7.5-:7.5) =("total count")/1`

,.......................................................................................................................

`=>("total count")/1 = 17/1`

Thus 17 purses were sold