Mayank buys some candies for Rs a dozen and an equal number of different candies for Rs a dozen. He sells all for Rs a dozen and makes a profit of Rs . How many dozens of candies did he buy altogether?
Mayank buys some candies for Rs a dozen and an equal number of different candies for Rs a dozen. He sells all for Rs a dozen and makes a profit of Rs . How many dozens of candies did he buy altogether?
Solution
Mayank buys two types of candies:
Type 1: Some dozens at Rs 15 per dozen
Type 2: Equal number of dozens at Rs 12 per dozen
Selling price: Rs 16.50 per dozen for all candies
Total profit: Rs 150
We need to find the total dozens of candies bought.
Let's say Mayank buys x dozens of each type of candy.
The problem states "equal number of different candies," so if he buys x dozens of the first type, he also buys x dozens of the second type.
Total candies bought = x + x = 2x dozens
Since Mayank buys equal quantities of both types, we can find the average cost:
Average cost per dozen =
Average cost per dozen =
When buying equal quantities of two items, the average cost is simply the arithmetic mean of their individual costs.
Profit per dozen = Selling price - Average cost price
Profit per dozen = 16.50 - 13.50 = Rs 3 per dozen
We know:
Profit per dozen = Rs 3
Total profit = Rs 150
Using the formula: Total profit = Profit per dozen × Number of dozens sold
Number of dozens sold = dozens
Mayank bought 50 dozens of candies altogether.
When buying equal quantities at different prices, we find the average cost, calculate profit per unit, then divide total profit by profit per unit to get the total quantity.