Question

The total weight of 18 non-identical items is 1170 kg. One item of weight 82kg is removed from them. Then, the average weight of remaining items, is

• A. 58 kg
• B. 60 kg
• C. 62 kg
• D. 64 kg

Hint:

Always double check the "Number of items." A common mistake is to divide by the original number (18) instead of the new number (17).

Answer 1

The Correct Option is D

Concept: The average weight is defined as the total weight of all items divided by the number of items. When an item is removed, both the total weight and the total count of items decrease. \[ \text{New Average} = \frac{\text{Total Weight} - \text{Weight of removed item}}{\text{Total Number of items} - 1} \]

Step 1: Calculate the remaining total weight.
Initial total weight = 1170 kg. One item weighing 82 kg is removed. \[ \text{Remaining Weight} = 1170 - 82 \] \[ \text{Remaining Weight} = 1088 \text{ kg} \]

Step 2: Calculate the remaining number of items.
Initial count = 18 items. One item is removed. \[ \text{Remaining Count} = 18 - 1 = 17 \text{ items} \]

Step 3: Find the new average.
Divide the new total weight by the new count: \[ \text{Average} = \frac{1088}{17} \] Performing the division: \[ 1088 \div 17 = 64 \] Thus, the average weight of the remaining items is 64 kg. Final Answer: Option D