Mary purchased a bottle of dragonfruit syrup to make drinks. She used ⁵₉ of the syrup in January. She then used the remaining syrup in February and March in the ratio 1 : 2. Given that the amount of the dragonfruit syrup used in January was 0.33 ℓ more than that in February, how many millilitres of dragonfruit syrup did the bottle contain at first?

January	February	March	Total
5x3	4x3		9x3
	1x4	2x4
15 u	4 u	8 u	27 u

Total volume of February and March is combined repeated identity.  Make the total volume of February and March the same.  LCM of 4 and 3 is 12.

Volume of more dragonfruit syrup in the bottle used in January than February
= 15 u - 4 u
= 11 u

11 u = 0.33 

1 u = 0.33 ÷ 11 = 0.03

Amount of dragonfruit syrup in the bottle at first
= 27 u
= 27 x 0.03
= 0.81 ℓ

1 ℓ = 1000 mℓ

Amount of dragonfruit syrup in the bottle at first
= 0.81 x 1000
= 810 mℓ

Answer(s): 810 mℓ