Let's find the total capacity of the bottle step by step.

Step 1: Define Variables

Let $C$ be the total capacity of the bottle in litres.

Step 2: Calculate Initial Amount of Water

Initially, the bottle is $\frac{7}{8}$ full, so the initial amount of water in the bottle is:

$\text{Initial water} = \frac{7}{8}C$

Step 3: Calculate Remaining Water After Drawing

When $1 \frac{1}{2}$ litres (which is $\frac{3}{2}$ litres) of water is drawn, the remaining water is:

$\text{Remaining water} = \frac{7}{8}C - \frac{3}{2}$

This remaining water makes the bottle $\frac{1}{24}$ full.

Step 4: Set Up the Equation

Since the remaining water is $\frac{1}{24}$ of the total capacity, we set up the equation:

$\frac{7}{8}C - \frac{3}{2} = \frac{1}{24}C$

Step 5: Solve for $C$

Multiply both sides by 24 to clear the fractions:

$24 \left(\frac{7}{8}C - \frac{3}{2}\right) = C$

Simplify the expression inside the parentheses:

$24 \times \frac{7}{8}C - 24 \times \frac{3}{2} = C$

$21C - 36 = C$

Move all terms involving $C$ to one side:

$21C - C = 36$

$20C = 36$

$C = \frac{36}{20} = 1.8 \text{ litres}$

Step 6: Convert Capacity to Millilitres

Since 1 litre = 1000 millilitres:

$C = 1.8 \times 1000 = 1800 \text{ millilitres}$

Final Answer

The capacity of the bottle is 1800 millilitres.

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Would you like to see more details, or do you have any questions?

Here are 5 related questions to explore:

1. What fraction of the bottle is left if 1 litre of water is drawn from it?
2. How would the problem change if the bottle was 3/4 full instead?
3. What would be the capacity if the remaining water was $\frac{1}{12}$ full?
4. How much water needs to be drawn for the bottle to be half full?
5. How can you convert between different units of volume, like litres to gallons?

Tip: Always double-check unit conversions to avoid errors, especially when switching between litres and millilitres!