Shiyun purchased a bottle of syrup. She used ⁵₇ of the syrup in January. She then used the remaining syrup in February and March in the ratio 4 : 5. Given that the amount of the syrup used in March was 1.05 ℓ less than that in January, how many millilitres of syrup did the bottle contain at first?

January	February	March	Total
5x9	2x9		7x9
	4x2	5x2
45 u	8 u	10 u	63 u

Total volume of February and March is combined repeated identity. Make the total volume of February and March the same. LCM of 2 and 9 is 18.

Volume of less syrup syrup in the bottle used in March than January
= 45 u - 10 u
= 35 u

35 u = 1.05 

1 u = 1.05 ÷ 35 = 0.03

Amount of syrup in the bottle at first
= 63 u
= 63 x 0.03
= 1.89 ℓ

1 ℓ = 1000 mℓ

Amount of syrup in the bottle at first
= 1.89 x 1000
= 1890 mℓ

Answer(s): 1890 mℓ