Final answer:
The calculation of profit and loss for the cosmetic shopkeeper shows a 25% profit made on selling lip guards, calculated using the difference between total revenue and total cost, then finding the percentage relative to the cost.
Step-by-step explanation:
The subject of this question is Mathematics, specifically related to the topic of profit and loss calculations. To find the profit or loss percentage of the cosmetic shopkeeper, we first calculate the total cost and total revenue, then we determine the difference between them to find profit or loss. Then we use this profit or loss to calculate the percentage relative to the cost.
A gross of lip guard means the shopkeeper bought 144 lip guards (since one gross equals 144 items). The total cost is Rs 2880. Selling each lip guard at Rs 25, the shopkeeper would get a total revenue of 144 * Rs 25 = Rs 3600.
Profit is calculated as Total Revenue minus Total Cost:
Profit = Rs 3600 - Rs 2880 = Rs 720.
To find the profit percentage, we use the formula:
Profit Percentage = (Profit / Total Cost) * 100.
Thus, Profit Percentage = (Rs 720 / Rs 2880) * 100 = 25%.
Therefore, the shopkeeper made a 25% profit from selling the lip guards.