​The average cost of 16 items is ₹59. Four items with an average price of ₹60 are returned and three other items costing ₹ 39 , ₹ 49 and ₹ 40 are also returned. Find the new average. ​

Correct option is B

Given:

1. The average cost of 16 items = ₹59.

2. Four items with an average price of ₹60 are returned.

3. Three other items with individual costs of ₹39, ₹49, and ₹40 are also returned.

4. Find the new average.

Formula Used:

1. Total cost of items:

$$\text{Total cost} = \text{Average cost} \times \text{Number of items}$$​

2. Total cost of the items returned:

Total cost of returned items = 4 \times 60 + (39 + 49 + 40)

3. New total cost:

New total cost = Original total cost - Total cost of returned items

4. New number of items:

New number of items = Original number of items - Number of returned items

5. New average:

New average = $$\frac{\text{New total cost}}{\text{New number of items}}$$​

Solution:

1. Calculate the original total cost:

Original total cost = 59 $$\times$$​ 16 = 944

2. Calculate the total cost of returned items:

Total cost of returned items = $$4 \times 60 + (39 + 49 + 40) = 240 + 128 = 368$$​

3. Calculate the new total cost:

New total cost = 944 - 368 = 576

4. Calculate the new number of items:

New number of items = 16 - (4 + 3) = 9

5. Calculate the new average:

New average = $$\frac{576}{9} = 64$$​

Final Answer:

The new average is ₹64.