Download Math7U5L3_homework

Name:
Unit: Math 7 Unit 5
Period:
Date:
Course:
Lesson: Lesson 3 Homework
Homework
Part I: REVIEW FROM 5th and 6th GRADE:
MODE: The data that occurs with the greatest frequency, or “the most”.
MEAN: The mean is a measure of center. To find the mean of a set of data, add all the
values together, then divide by number of values in the data set.
The mean of 16, 7, 0, 24, 4, 19, and 7 is calculated by: adding all of the numbers to get
77 then dividing 77 by 7 (the number of data pieces) to get a mean = 11
MEDIAN: The median is a measure of center. To find the median of a set of data,
arrange the data in order from least to greatest. If there are an odd number of values,
the median will be the middle value. If there is an even number of values, the median will
be the midpoint between the values in the middle.
Example 1: Find the median of 33, 37, 10, 15, 7, 3, 0, 6, and 7. Arrange in order:
0, 3, 6, 7, 7, 10, 15, 33, and 37. There are 9 data points. The middle (median) value is
the 5th one, which is 10.
Example 2: Find the median of 15, 6, 7, 42, 6, and 11. Arrange in order: 6, 6, 7,
11, 15, and 42. There are 6 data points. The median is the midpoint between 8 and 11,
so the median = 9.5. The midpoint between two data points can be found by finding the
average of the two points. (8 + 11)/2 = 9.5
Find the mean for the following data sets:
1. 2, 6, 1, 8, 10, 2, 3, 6
2. 24, 14, 8, 9, 6, 5, 18, 10, 16,
22
Find the median for the following data sets:
3. 12, 8, 7, 6, 9, 5, 1, 2, 3
4. 5, 1.6, 3, 8, 7, 11, 15.5, 18,
20, 11
5. A survey was conducted where respondents gave their favorite summer
temperature (in degrees Fahrenheit). The results are as follows: 65, 74,
66, 74, 76, 67,
Name:
Unit: Math 7 Unit 5
Period:
Date:
Course:
Lesson: Lesson 3 Homework
Homework
74, 70, 73, 68, 64, 80, 85, and 90. Find the mean temperature from the
survey. Round your answer to the nearest degree.
20 males and 20 females were asked to approximate the number of times
that they viewed Facebook each day. Histograms for the data are shown
below.
6. Based on those that were surveyed, which group had a greater median,
the boys or the girls? Explain your answer.
7. Why would mode not be a good measure of center for the female data
distribution?
8. Create your own dot plots below that follow these rules:
Name:
Period:
Date:
Course:
Lesson: Lesson 3 Homework
Homework
Unit: Math 7 Unit 5
Rule #1: Dot Plot #1 must have a larger spread
Rule #2: Dot Plot #2 must have a greater measure of center
DOT PLOT #1
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DOT PLOT #2
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Name:
Period:
Date:
Course:
Lesson: Lesson 3 Homework
Homework
Unit: Math 7 Unit 5
Part II
Students
Number of pens
and pencils
Deviation from
the Mean
number – mean
Absolute
deviation from
the mean
|number – mean|
Student 1
Student 2
Student 3
Student 4
Student 5
4
2
7
4
3
TOTAL:
MEAN:
TOTAL:
(MAD):
1. A group of students were surveyed and we recorded the number of pens and
pencils that each one had in his or her desk. Find the mean of the data. What
does the mean represent?
Mean Absolute Deviation (Review from 6th Grade): The mean absolute deviation (MAD) is a
measure of variation in a set of numerical data. It is computed by adding the distances between
each data value and the mean, then dividing by the number of data values.
2. Find the mean absolute deviation for the data you collected.
Name:
Unit: Math 7 Unit 5
Period:
Date:
Course:
Lesson: Lesson 3 Homework
Homework
3. In problem #2 above, you found the mean absolute deviation for the data. On the
number line below, mark the position of the mean. Put large bracket symbols [ ]
above and below the mean at a distance of one mean absolute deviation.
4. For another group of students were surveyed and they had a mean of 5 and a
MAD of 0.4. Mark the position of the mean on the number line below. Put large
bracket symbols [ ] above and below the mean at a distance of one mean
absolute deviation.
5. Is the MAD for the first group higher or lower than the second group? What does
it mean if a group has a higher MAD? What does it mean if a group has a lower
MAD?