Sally purchased notebooks at $2.50 apiece, and pens at $1.00 apiece. If she bought a total of 12 items for $24.00, how many notebooks did she buy?

Sally purchased notebooks at $2.50 apiece, and pens at $1.00 apiece. If she bought a total of 12 items for $24.00, how many notebooks did she buy?

The equations area:

x+y=12; x=number of notebooks and y= number of pens

2.5x + y = 24

Y=24 - 2.5x

x + 24 - 2.5x =12

12 = 1.5x

x=8 notebooks

y = 4 pens