To find the trade discount, we first need to compute the single equivalent discount for the discount rates of 20%, 10%, and 5%. We apply each discount successively on the remaining price after the previous discount has been applied.

Step-by-step process:

1. List price = $9,000

2. First discount (20%):
   $\text{New price} = 9,000 \times (1 - 0.20) = 9,000 \times 0.80 = 7,200$

3. Second discount (10%):
   $\text{New price} = 7,200 \times (1 - 0.10) = 7,200 \times 0.90 = 6,480$

4. Third discount (5%):
   $\text{New price} = 6,480 \times (1 - 0.05) = 6,480 \times 0.95 = 6,156$

The final price after applying all discounts is $6,156.

Trade Discount:

$\text{Trade Discount} = 9,000 - 6,156 = 2,844$

Thus, the total trade discount is $2,844.

Would you like more details on any step, or further clarification?

Here are five related questions:

1. How would the trade discount change if the last discount was 7% instead of 5%?
2. What would be the equivalent single discount rate for the combined 20/10/5 trade discounts?
3. How does the order of applying discounts affect the final price?
4. What is the formula for calculating the single equivalent discount for multiple trade discounts?
5. How would the final price change if the initial list price was $12,000 instead of $9,000?

Tip: Always apply trade discounts sequentially rather than adding them together directly!