The price of a product is reduced by 25%, but the daily sale of the article is increased by 30%. Find the net effect on the daily sale.

Question: The price of a product is reduced by 25%, but the daily sale of the article is increased by 30%. Find the net effect on the daily sale.

Solution:
We can say that,
Total Sale = the price of one unit × no. of units sold

Let
the initial price of product = 100, sale =100 items.
Then, Total Sale = 100 × 100 = 10000

ATQ,
price reduces to 25%.
So, the new price = 100 - 25 = 75
Sale increase to 30%,
So, the new sale = 100 + 30 = 130
Now, the new total sale = 75 × 130 = 9750

Difference = 10000 - 9750 = 250
% net effect = (diff/original)× 100
= (250/10000) × 100 = 2.5
So, the net effect on daily sale = 2.5% decrease