Given:
- Faulty weight of 1 kg measures 940 g
- Faulty weight of 500 g measures 470 g

To Find:
- Percentage profit of the dishonest shopkeeper

Solution:
Step 1: Calculate the actual weight of 1 kg and 500 g weights
- Actual weight of 1 kg weight = 1000 g
- Actual weight of 500 g weight = 500 g

Step 2: Calculate the difference between the actual and measured weights
- Difference for 1 kg weight = 1000 g - 940 g = 60 g
- Difference for 500 g weight = 500 g - 470 g = 30 g

Step 3: Calculate the cost price of 1 kg and 500 g weights
- Cost price for 1 kg weight = Cost price of 1 g * Actual weight of 1 kg
= (1/100) * 1000 = 10
- Cost price for 500 g weight = Cost price of 1 g * Actual weight of 500 g
= (1/100) * 500 = 5

Step 4: Calculate the selling price of 1 kg and 500 g weights
- Selling price for 1 kg weight = Cost price for 1 kg weight + Profit
= 10 + 60 = 70
- Selling price for 500 g weight = Cost price for 500 g weight + Profit
= 5 + 30 = 35

Step 5: Calculate the total cost price and total selling price
- Total cost price = Cost price for 1 kg weight + Cost price for 500 g weight
= 10 + 5 = 15
- Total selling price = Selling price for 1 kg weight + Selling price for 500 g weight
= 70 + 35 = 105

Step 6: Calculate the percentage profit
- Percentage profit = ((Total selling price - Total cost price) / Total cost price) * 100
= ((105 - 15) / 15) * 100
= (90 / 15) * 100
= 6 * 100
= 600 / 100
= 6%

Hence, the dishonest shopkeeper has a percentage profit of 6%. Answer option (b) is correct.