Alex wants to mark a jar so that it holds four 300 mL cups of liquid. How many times should he pour from his 100 mL cup to measure four 300 mL cups of liquid?
Four 300-mL cups = 4 x 300 mL = 1200 mL.
To measure 1200 mL using a 100-mL cup, he has to pour 1200 mL÷100 mL = 12 times.