Answer:
A. On average, 8th graders take out 2 more books a day than 7 graders.
Step-by-step explanation:
Given
The above table
Required
Truth statement from the given list of options (A - D).
To get which of the options that is true or false, we'll have to test each condition.
A. On average, 8th graders take out 2 more books a day than 7 graders.
This condition refers to average (mean); So, we'll have to calculate the mean of both graders.
Mean is calculated as (∑x)/n
Where x = books read on each day's and n = number of days (5)
For the 7th graders,
Mean = (6 + 6 + 7 + 11 + 5)/5
Mean = 35/5
Mean = 7
For 8th graders,
Mean = (4 + 5 + 10 + 10 + 16)/5
Mean = 45/5
Mean = 9
The mean of the 8th graders is 2 more than the mean of the 7yh graders.
This statement is true.
B. 8th graders take out fewer books than 7th graders.
Here, we only need the sum of books read by 7th and 8th graders.
For 7th graders
Total = 6 + 6 + 7 + 11 + 5
Total = 35 books
For 8th graders
Total = 4 + 5 + 10 + 10 + 16
Total = 45 books
This statement is false because 8th graders take more books (45) than 7th graders (35)
C. The median of the sample of books of 7th graders is 7.
To get the median value, first the data has to be arranged (in ascending or descending order).
Arranging the books read by 7th graders in ascending order
Books; 5, 6, 6, 7, 11
The Median is the data at the middle.
In this case, it's 6.
This statement is false because the median is not 7
D. The range of books in the sample is twice as great for 7th graders as compared to 8th graders.
Range is calculated by subtracting least value from highest value.
For the 7th graders.
Least = 5
Highest = 11
Range = 11 - 5
Range = 6
For the 8th graders
Least = 4
Highest = 16
Range = 16 - 4
Range = 12
This statement is false.
Because the range of the 7th graders is not twice as great as compared to the range of the 8th graders.
From option A to D, only option A is right.
