Answer:
25
Step-by-step 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.