In a shop, a trader has 1500 kg of toor dal in stock.\nIf he sells 4.5% of this toor dal during the day, what quantity (in kilograms) of toor dal is sold?

Introduction / Context:
This problem tests a very common application of percentages to quantities, in this case kilograms of toor dal. You are asked to find what 4.5% of a given weight is. Such calculations appear frequently in questions on inventory, stock, agriculture, and business, and mastering them builds a strong base for more complex percentage applications.

Given Data / Assumptions:

• Total stock of toor dal = 1500 kg.
• Percentage sold = 4.5% of the total stock.
• The remaining stock is not required; only the sold quantity is asked.
• We assume all measurements are in kilograms and represent exact values.

Concept / Approach:
To find a percentage of a quantity, we use the basic formula: Percentage of a quantity = (percentage / 100) * quantity. Here, the percentage is 4.5 and the quantity is 1500 kg. We convert 4.5% to a decimal or fraction and then multiply by 1500. Breaking the calculation into smaller steps (like finding 1% or 0.5%) makes mental math easier and reduces errors.

Step-by-Step Solution:
Step 1: Express 4.5% as a fraction over 100: 4.5% = 4.5 / 100. Step 2: Quantity sold = (4.5 / 100) * 1500. Step 3: Compute 4.5 * 1500 first: 4.5 * 1500 = 4.5 * (15 * 100) = (4.5 * 15) * 100. Step 4: 4.5 * 15 = 67.5, so 4.5 * 1500 = 67.5 * 100 = 6750. Step 5: Now divide by 100: 6750 / 100 = 67.5 kg. Step 6: Therefore, the trader sells 67.5 kg of toor dal.

Verification / Alternative check:
You can also use the idea of 1%. One percent of 1500 kg is 15 kg. Then 0.5% is half of 1%, which is 7.5 kg. So 4.5% = 4% + 0.5%. Four percent of 1500 is 4 * 15 = 60 kg, and 0.5% is 7.5 kg. Adding them: 60 + 7.5 = 67.5 kg. This mental math approach confirms the earlier result exactly.

Why Other Options Are Wrong:
64.5 kg: Slightly less than the correct value; this can arise from miscomputing 4.3% or a minor arithmetic slip.
63.5 kg: Clearly lower than 4.5% of 1500 and not supported by correct percentage calculation.
70 kg: Slightly more than 4.5%; corresponds to about 4.67% of 1500, not 4.5%.
60 kg: This is exactly 4% of 1500, not 4.5%, so it underestimates the sold quantity.

Common Pitfalls:
A common error is to confuse 4.5% with 45% and mistakenly compute a much larger value. Another pitfall is rounding too early or mishandling the decimal, for example treating 4.5 as 4.05. Always write the percentage clearly as percentage / 100 and take care when multiplying with decimals. Breaking down into 1% and 0.5% chunks also helps avoid mistakes.

Final Answer:
The quantity of toor dal sold is 67.5 kg.