Pamela purchased a bottle of persimmon syrup to make drinks. She used ¹₅ of the syrup in April. She then used the remaining syrup in May and June in the ratio 1 : 6. Given that the amount of the persimmon syrup used in April was 0.12 ℓ more than that in May, how many millilitres of persimmon syrup did the bottle contain at first?

April	May	June	Total
1x7	4x7		5x7
	1x4	6x4
7 u	4 u	24 u	35 u

Total volume of May and June is combined repeated identity.  Make the total volume of May and June the same.  LCM of 4 and 7 is 28.

Volume of more persimmon syrup in the bottle used in April than May
= 7 u - 4 u
= 3 u

3 u = 0.12 

1 u = 0.12 ÷ 3 = 0.04

Amount of persimmon syrup in the bottle at first
= 35 u
= 35 x 0.04
= 1.4 ℓ

1 ℓ = 1000 mℓ

Amount of persimmon syrup in the bottle at first
= 1.4 x 1000
= 1400 mℓ

Answer(s): 1400 mℓ