1. Anna recorded the number of hours she studied for her exams over five days: 4, 6, 8, 10, and 12 hours. What is the average number of hours Anna studied per day?
2. A group of friends compared the number of books they read last month. They read 15, 20, 25, and 30 books respectively. What is the mean number of books read?
3. James recorded the scores he got in six math quizzes: 2, 3, 5, 7, 11, and 13. What was James' average quiz score?
4. During a week, a student scored 100, 90, 80, 85, and 95 in his daily spelling tests. What is the mean score for the week?
5. A gardener recorded the number of flowers blooming in her garden over five days: 9, 7, 5, 3, and 1. What is the average number of flowers blooming per day?
Answer (1)
To find the average, or mean, of a set of numbers, you add up all the numbers and then divide by the number of numbers.
Anna's Study Hours:
Add the numbers: 4 + 6 + 8 + 10 + 12 = 40
Since there are 5 numbers (days), divide the total by 5: 5 40 = 8
So, Anna studied an average of 8 hours per day.
Books Read by Friends:
Add the numbers: 15 + 20 + 25 + 30 = 90
There are 4 people, so divide by 4: 4 90 = 22.5
On average, they read 22.5 books each.
James' Quiz Scores:
Add the scores: 2 + 3 + 5 + 7 + 11 + 13 = 41
There are 6 quiz scores, divide by 6: 6 41 ≈ 6.83
James' average quiz score is approximately 6.83.
Spelling Test Scores:
Add the scores: 100 + 90 + 80 + 85 + 95 = 450
There are 5 scores, so divide by 5: 5 450 = 90
The mean score for the week is 90.
Flowers Blooming in the Garden:
Add the numbers: 9 + 7 + 5 + 3 + 1 = 25
There are 5 days, so divide by 5: 5 25 = 5
The average number of flowers blooming per day is 5.
Understanding how to calculate the mean helps you summarize data with a single number representing the central tendency of the data set.
