Gun - powder contains `75%` nitre, `10%` sulphur and the rest of it is charcoal. Find the quantity of charcoal in 8 kg of gun-powder.

Answer

To find the quantity of charcoal in 8 kg of gunpowder, we can follow these steps:

### Step 1: Determine the percentage of charcoal in gunpowder.
Gunpowder contains:
- 75% nitre
- 10% sulphur

To find the percentage of charcoal, we subtract the sum of the percentages of nitre and sulphur from 100%.

\[ \text{Percentage of charcoal} = 100\% - (75\% + 10\%) = 100\% - 85\% = 15\% \]

### Step 2: Calculate the quantity of charcoal in 8 kg of gunpowder.
Now that we know that charcoal makes up 15% of the gunpowder, we can calculate the quantity of charcoal in 8 kg.

\[ \text{Quantity of charcoal} = 15\% \text{ of } 8 \text{ kg} \]

To calculate this, we convert the percentage to a fraction and multiply it by the total weight:

\[ \text{Quantity of charcoal} = \frac{15}{100} \times 8 \text{ kg} \]

### Step 3: Perform the calculation.
Now we can perform the multiplication:

\[ \text{Quantity of charcoal} = \frac{15 \times 8}{100} = \frac{120}{100} = 1.2 \text{ kg} \]

### Final Answer:
Thus, the quantity of charcoal in 8 kg of gunpowder is **1.2 kg**.

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