An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (2)
Calculate the relative frequency for each sport by dividing its frequency by the total number of students (25).
Basketball: 25 4 = 0.16
Football: 25 7 = 0.28
Lacrosse: 25 3 = 0.12
Soccer: 25 8 = 0.32
Volleyball: 25 3 = 0.12
The correct relative frequency table is:
Basketball
Football
Lacrosse
Soccer
Volleyball
0.16
0.28
0.12
0.32
0.12
0.16 , 0.28 , 0.12 , 0.32 , 0.12
Explanation
Understand the problem We are given a frequency table of students' favorite sports and asked to find the correct relative frequency table. The total number of students surveyed is 25.
Calculate relative frequencies To find the relative frequency for each sport, we divide the frequency of that sport by the total number of students.
Basketball The relative frequency for Basketball is 25 4 = 0.16 .
Football The relative frequency for Football is 25 7 = 0.28 .
Lacrosse The relative frequency for Lacrosse is 25 3 = 0.12 .
Soccer The relative frequency for Soccer is 25 8 = 0.32 .
Volleyball The relative frequency for Volleyball is 25 3 = 0.12 .
Final Answer The correct relative frequency table is:
Basketball
Football
Lacrosse
Soccer
Volleyball
0.16
0.28
0.12
0.32
0.12
Examples
Understanding relative frequencies is useful in many real-world scenarios. For example, if a store wants to know which products are most popular among its customers, it can track the frequency of sales for each product. The relative frequency then tells the store the proportion of total sales that each product represents, which can inform decisions about inventory and marketing.
A current of 15.0 A flowing for 30 seconds results in about 2.81 × 1 0 21 electrons passing through the device. This is calculated by first determining the total charge and then dividing by the charge of a single electron. Thus, a significant number of electrons flow for that amount of current and time.
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