Min purchased a bottle of kiwi syrup to make drinks. She used ⁵₇ of the syrup in March. She then used the remaining syrup in April and May in the ratio 3 : 4. Given that the amount of the kiwi syrup used in March was 1.45 ℓ more than that in April, how many millilitres of kiwi syrup did the bottle contain at first?

March	April	May	Total
5x7	2x7		7x7
	3x2	4x2
35 u	6 u	8 u	49 u

Total volume of April and May is combined repeated identity.  Make the total volume of April and May the same.  LCM of 2 and 7 is 14.

Volume of more kiwi syrup in the bottle used in March than April
= 35 u - 6 u
= 29 u

29 u = 1.45 

1 u = 1.45 ÷ 29 = 0.05

Amount of kiwi syrup in the bottle at first
= 49 u
= 49 x 0.05
= 2.45 ℓ

1 ℓ = 1000 mℓ

Amount of kiwi syrup in the bottle at first
= 2.45 x 1000
= 2450 mℓ

Answer(s): 2450 mℓ