An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (2)
Find the number of viewers in the 16-25 age group who gave the movie a poor rating: 7.
Find the total number of viewers in the 16-25 age group: 113.
Calculate the percentage: 113 7 × 100 ≈ 6.19 .
The percentage of the audience from the 16-25 age group who gave the movie a poor rating is 6.19% .
Explanation
Understand the problem and provided data We are asked to find the percentage of the audience from the 16-25 age group who gave the movie a poor rating. From the table, we can see that 7 viewers in the 16-25 age group gave the movie a poor rating. The total number of viewers in the 16-25 age group is 113.
Calculate the percentage To find the percentage, we divide the number of viewers who gave a poor rating by the total number of viewers in that age group, and then multiply by 100.
Perform the calculation The percentage is calculated as follows: 113 7 × 100 The result of this calculation is approximately 6.1946902654867255 .
Round the result and conclude Rounding to two decimal places, we get 6.19% .
Examples
Understanding percentages is crucial in many real-life situations. For example, when analyzing customer feedback for a product, you might want to know what percentage of customers rated the product poorly. This helps in identifying areas for improvement. Similarly, in finance, understanding percentage changes in stock prices or interest rates is essential for making informed decisions.
In 30 seconds, a current of 15.0 A flows a total charge of 450 Coulombs. This charge corresponds to about 2.81 x 10^21 electrons flowing through the device. Therefore, approximately 2.81 billion billion electrons pass through the device in that time.
;
