Sabrina purchased a bottle of sauce. She used ³₅ of the sauce in March. She then used the remaining sauce in April and May in the ratio 1 : 2. Given that the amount of the sauce used in May was 0.7 ℓ less than that in March, how many millilitres of sauce did the bottle contain at first?

March	April	May	Total
3x3	2x3		5x3
	1x2	2x2
9 u	2 u	4 u	15 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 3 is 6.

Volume of less sauce syrup in the bottle used in May than March
= 9 u - 4 u
= 5 u

5 u = 0.7 

1 u = 0.7 ÷ 5 = 0.14

Amount of sauce in the bottle at first
= 15 u
= 15 x 0.14
= 2.1 ℓ

1 ℓ = 1000 mℓ

Amount of sauce in the bottle at first
= 2.1 x 1000
= 2100 mℓ

Answer(s): 2100 mℓ