Finding the unit rate is to work out how many doughnuts baked for every one minute
1 dozen = 12 units
4 dozen = 12 × 4 = 48 units
18 minutes ⇒ 48 doughnuts
Divide 18 minutes by 18 to get 1 minute
Because we divide 18 minutes by 18, we will also divide 48 by 18
18 ÷ 18 ⇒ 48 ÷ 18
1 minute ⇒ 2.67 doughnuts
The rate of doughnuts production is 2.67 doughnuts for every minute