PSLE
Marion had a bottle of soy milk. She drank 760 mℓ of soy milk in the morning and ²₅ of remaining soy milk in the afternoon. After that, there was ¹₃ a bottle of soy milk left. How much of the soy milk did she drink in the afternoon?
Fraction of the remaining soy milk left in the end
= 1 - ²₅
= ³₅

The remaining soy milk left in the end is equal to ¹₃ of the bottle of soy milk.
Make numerators the same.
LCM of 3 and 1 is 3.
 
³₅ of the remaining soy milk = ¹₃ of the total soy milk
³₅ of the remaining soy milk = ³₉ of the total soy milk

Volume of soy milk that she drank in the morning
= 9 u - 5 u
= 4 u

4 u = 760

1 u = 760 ÷ 4 = 190

Volume of soy milk that she drank in the afternoon
= 2 u
= 2 x 190
= 380 mℓ

Answer(s): 380 mℓ