Kylie purchased a bottle of maple syrup. She used ⁷₉ of the maple syrup in April. She then used the remaining maple syrup in May and June in the ratio 1 : 2. Given that the amount of the maple syrup used in June was 1.02 ℓ less than that in April, how many millilitres of maple syrup did the bottle contain at first?

April	May	June	Total
7x3	2x3		9x3
	1x2	2x2
21 u	2 u	4 u	27 u

Total volume of May and June is combined repeated identity. Make the total volume of May and June the same. LCM of 2 and 3 is 6.

Volume of less maple syrup syrup in the bottle used in June than April
= 21 u - 4 u
= 17 u

17 u = 1.02 

1 u = 1.02 ÷ 17 = 0.06

Amount of maple syrup in the bottle at first
= 27 u
= 27 x 0.06
= 1.62 ℓ

1 ℓ = 1000 mℓ

Amount of maple syrup in the bottle at first
= 1.62 x 1000
= 1620 mℓ

Answer(s): 1620 mℓ