Interpret each term individually and then decipher what it means to add them together.
The total cost for school supplies.
Practice makes perfect
To find how the given expression is related to Sandi's scenario, let's consider each term individually. According to the exercise, Sandi buys 5 fewer packages of pencils than p packages of pens. This means that we should subtract 5 from p to get the number of packages of pencils she will buy.
Expression
Meaning
p
Number of packages of pens
p-5
Number of packages of pencils
Next, we are given the price of a package of pens and the price of a package of pencils.
Expression
Meaning
$ 3
Cost per package of pens
$ 2.25
Cost per package of pencils
This means that we can calculate how much Sandi is spending by multiplying the number of pens and pencils by their respective prices.
Expression
Meaning
$ 3* p
Total cost of p pens
$ 2.25* ( p-5)
Total cost of ( p-5) pencils
Remember, the expression $3* p can also be written as the term 3p. Similarly, $2.25* (p-5) can be expressed as the term 2.25(p-5). The given expression,
3p + 2.25(p-5),
is the sum of the two terms we found above. Therefore, the expression represents the total amount Sandi will spend on p packages of pens and (p-5) packages of pencils.
