Statistics：练习题

The following table shows the number of apples sold by a fruit stall over 4 days:
Monday: 48
Tuesday: 52
Wednesday: 45
Thursday: 55
What is the average (mean) number of apples sold per day?

In a bar chart, the horizontal axis represents different types of juice sold, and the vertical axis represents the number of bottles. If the bar for "Orange Juice" is 14 cm tall and the scale is 1 cm = 8 bottles, how many bottles of orange juice were sold?

A group of students recorded their test scores: 65, 72, 85, 90, 72, 85, 65, 85. If they want to represent this data using a bar chart where the vertical axis represents the frequency and the scale is 2 cm = 1 student, how tall will the bar be for the score that appears most often (the mode)?

The table below shows the number of goals scored by a football team in 4 matches:
Match 1: 3
Match 2: 0
Match 3: 4
Match 4: 1
What is the average (mean) number of goals scored per match?

The following data shows the temperature recorded at noon over five days: \( 22^{\circ}C, 24^{\circ}C, 21^{\circ}C, 25^{\circ}C, \) and \( X^{\circ}C \). If the average temperature for these five days is \( 23^{\circ}C \), what is the value of \( X \)?

The number of books read by four students is: 3, 7, 7, and 11. What is the average (mean) number of books read?

In a bar chart, the scale on the vertical axis is \(2\text{ cm} = 10\text{ units}\). If the bar for "Category A" is \(7\text{ cm}\) tall, how many units does it represent?

The average marks of 4 students in a test is 78. If a fifth student joins and scores 83 marks, what is the new average mark of the 5 students?

A bar chart represents the number of students in different clubs:
Art: 15 students
Music: 25 students
Sports: 40 students
Drama: 10 students
(a) What is the total number of students in all clubs?
(b) If a bar chart is drawn where 1 cm on the vertical axis represents 5 students, what is the height of the 'Sports' bar?
(c) What is the mean (average) number of students per club?

A delivery company has a fleet of vehicles. The distribution of vehicle types is shown below:
Vans: 24
Trucks: 18
Motorcycles: 12
(a) If a bar chart is drawn to represent this data and the scale on the vertical axis is \(2\text{ cm} = 6\text{ vehicles}\), calculate the height of the bars for Vans and Motorcycles.
(b) What percentage of the total fleet are Trucks?
(c) If the company doubles the number of Motorcycles, what would be the new mean number of vehicles per type?