PSLE
Mrs Lim had a bottle of maple syrup. She used an equal amount of maple syrup each day. At the end of the fifth day, she had 1890 mℓ of maple syrup left. At the end of the eighth day, she had three-quarters of the bottle of maple syrup left. How many litres of maple syrup were there in the bottle at first?
Fraction of maple syrup used after three-quarters of the bottle was left
= 1 - ³₄
= ¹₄

¹₄ of the bottle → 8 days
1 bottle → 8 ÷ ¹₄ = 8 x ⁴₁ =  32 days

It takes 32 days to finish the whole bottle.

Number of days to use 1890 mℓ of maple syrup
= 32 - 5
= 27

27 days → 1890 mℓ

1 day → 1890 ÷ 27 = 70 mℓ

32 days → 32 x 70 = 2240 mℓ

1000 mℓ = 1 ℓ

2240 mℓ = 2240 ÷ 1000 = 2.24 ℓ

Volume of maple syrup in the bottle at first = 2.24 ℓ

Answer(s): 2.24 ℓ