Determine the better buy by comparing unit rates.

1. 20 pens for $1.60 or 25 pens for $2.25

2. 13 berries for $2.60 or 17 berries for $3.06

1. 20 pens for $1.60

2. 17 berries for $3.06

To find the better buy we have to find the cost per pen for each.

1. 20 pens for $1.60 - > 1.60/20 =.08 cents per pen.

25 pens for $2.25 - > 2.25/25 =.09 cents per pen.

The best buy is 20 pens for $1.60 because it's cheaper per pen.

2. 13 berries for $2.60 - > 2.60/13 =.20 cents per berry

17 berries for $3.06 - > 3.06/17 =.18 cents per berry

The best buy is 17 berries for $3.06 because it's cheaper per berry.