Question

Sentence.

A teacher needs to buy some red pens for $0.55 each and some board markers for
$1.50 each to last the semester. She spends a total of $46.30 on 41 items. How many
board markers did she buy?

Answer 1

25

Explanation:

We need to set up a system of equations, then solve for the number of board markers.

Let r represent red pens, let b represent board markers.

She has 41 items, so our first equation is r+b=41.

The total cost is $46.30, so our second equation is .55r+1.5b=46.3.

r+b=41

.55r+1.5b=46.3

Let's use substitution.

r+b=41

r=41-b

.55r+1.5b=46.3

.55(41-b)+1.5b=46.3

22.55-.55b+1.5b=46.3

22.55+.95b=46.3

.95b=23.75

b=25

He bought 25 board markers.