Gem purchased a bottle of chikoo syrup to make drinks. She used ¹₃ of the syrup in April. She then used the remaining syrup in May and June in the ratio 3 : 8. Given that the amount of the chikoo syrup used in April was 0.25 ℓ more than that in May, how many millilitres of chikoo syrup did the bottle contain at first?

April	May	June	Total
1x11	2x11		3x11
	3x2	8x2
11 u	6 u	16 u	33 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 11 is 22.

Volume of more chikoo syrup in the bottle used in April than May
= 11 u - 6 u
= 5 u

5 u = 0.25 

1 u = 0.25 ÷ 5 = 0.05

Amount of chikoo syrup in the bottle at first
= 33 u
= 33 x 0.05
= 1.65 ℓ

1 ℓ = 1000 mℓ

Amount of chikoo syrup in the bottle at first
= 1.65 x 1000
= 1650 mℓ

Answer(s): 1650 mℓ