The total cost price of 8 pens and 12 bottles together is Rs. 440. Find at what price 10 pens and 15 bottles should be sell to receive a profit of 20%.720 Rs.520 Rs.600 Rs.660 Rs.550 Rs.

To find the selling price of 10 pens and 15 bottles in order to make a profit of 20%, we need to follow these steps:

Step 1: Calculate the cost price of 1 pen and 1 bottle. To find the cost price of 1 pen, we divide the total cost price of 8 pens and 12 bottles by the total quantity of pens, which is 8. Cost price of 1 pen = Rs. 440 / 8 = Rs. 55

Similarly, to find the cost price of 1 bottle, we divide the total cost price by the total quantity of bottles, which is 12. Cost price of 1 bottle = Rs. 440 / 12 = Rs. 36.67 (approx.)

Step 2: Calculate the total cost price of 10 pens and 15 bottles. To find the total cost price of 10 pens, we multiply the cost price of 1 pen by 10. Total cost price of 10 pens = Rs. 55 * 10 = Rs. 550

To find the total cost price of 15 bottles, we multiply the cost price of 1 bottle by 15. Total cost price of 15 bottles = Rs. 36.67 * 15 = Rs. 550.05 (approx.)

Step 3: Calculate the selling price to make a profit of 20%. To calculate the selling price, we add the desired profit to the total cost price. Profit = 20% of the total cost price = 20/100 * (550 + 550.05) = Rs. 220.01 (approx.)

Selling price = Total cost price + Profit = 550 + 550.05 + 220.01 = Rs. 1320.06 (approx.)

Therefore, the selling price of 10 pens and 15 bottles to make a profit of 20% is approximately Rs. 1320.06.