To solve the problem, we need to determine the net effect of a price increase followed by a discount, both expressed in percentages.
- Price Increase: An upward change in price, expressed as a percentage of the original price.
- Discount: A reduction applied after the increase, on the increased price.
- Net Change Formula: When an increase of x% is followed by a decrease of y%, the net percentage change is given by:
\[ \text{Net \% change} = x - y - \frac{xy}{100} \]
- Increase = 25%
- Discount = 20%
\[ \text{Net \% change} = 25 - 20 - \frac{25 \times 20}{100} = 5 - 5 = 0\% \]
There is no net change in the price; the overall percentage change is 0%.
An electricity utility company charges ₹7 per kWh. If a 40-watt desk light is left on for 10 hours each night for 180 days, what would be the cost of energy consumption? If the desk light is on for 2 more hours each night for the 180 days, what would be the percentage-increase in the cost of energy consumption?
A pie chart shows the distribution of students across 5 faculties in a university. If 20% are in Arts, 25% in Science, 15% in Law, 30% in Engineering, and the rest in Commerce, what is the angle (in degrees) for Commerce?
What comes next in the series?
\(2, 6, 12, 20, 30, \ ?\)