45) A tin of biscuits has a mass of 1243g. When it is half full, its mass is 728g. What is the
mass of the tin when it is empty?
22) Rebecca bought 4 bottles of soft drink. Each bottle $1.65 and contained 1.25l of soft
drink. (a)How many times of soft drink did she buy?
(b) If she paid the cashier $10, how much change did she receive?