Student Manual
Math Ready . Unit 8 . Lesson 4

29
Task 12: Independent Practice for Lesson 3
Two golfers kept track of their scores over the course of a year. Their scores are given below. (All
courses played were 72 par)
Player 1: 85, 80, 78, 83, 83, 88, 72, 75, 79, 79
Player 2: 72, 71, 90, 95, 70, 88, 78, 78, 70, 90
Who is the better golfer and why? Explain your reasoning.
(Note: In golf, the lower score wins!)
Student Manual
Math Ready . Unit 8 . Lesson 4

30
Task #13: Explore
Give an example of a set of five positive numbers whose median is 10 and whose mean is larger
than 10.
Student Manual
Math Ready . Unit 8 . Lesson 5

31
Task #14: Mean and Median Investigation
Part 1: Consider the set of numbers {10, 15, 25, 30, 30, 50, 55, 55, 60, 80}
a.
Find the mean.
b.
Find the median.
Part 2: Now, replace the 80 with 800 to create a new set {10, 15, 25, 30, 30, 50, 55, 55, 60, 800}
c.
Find the mean.
d.
Find the median.
e.
What effect did changing 80 to 800 have on the mean and the median?
Student Manual
Math Ready . Unit 8 . Lesson 5

32
Task #15: Guided Notes
Definition
An
is any data point that is more than
1.5 times the Inner Quartile Range (IQR) away from either the lower or upper quartile.
{39, 51, 36, 39, 90, 55, 32, 61, 45, 53, 14}
1.
Complete the Five Number Summary for the data set above.
minimum =
lower quartile (Q
1
) =
median =
upper quartile (Q
3
) =
maximum =
2.
Calculate the Inner Quartile Range (IQR).
IQR = Q
3
– Q
1
=
3.
Check for outliers.
Q
1
– (1.5 x
IQR
) =
Q
3
+ (1.5 x
IQR
) =
4.
Does this data set contain any outliers? If so, list them.
Student Manual
Math Ready . Unit 8 . Lesson 5

33
Task #16: Celestial Bodies and Home Prices
1.
Calculate the mean and median for these distances. Would the typical distance of these celestial
bodies best be communicated using the mean or the median? Why?
2.
What impact do the very large values in the data set have on the mean?
3. Suppose that a sample of 100 homes in the metropolitan Phoenix area had a median sales price
of $300,000. The mean value of these homes was $1,000,000.
Explain how this could happen.
Why might the median price be more informative than the mean price in describing a typical
house price?
Student Manual
Math Ready . Unit 8 . Lesson 5
Object
Distance in light years
Moon
0.000000038
Venus
0.0000048
Jupiter
0.000067
Mars
0.0000076
Mercury
0.0000095
Syrius
8.6
Canopus
310
Saturn
0.00014

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Task #17: Lesson 5 Exit Ticket
Suppose the mean annual income for a sample of one hundred Minneapolis residents was $50,000.
Do you think the median income for this sample would have been greater than, equal to, or less than
$50,000? Explain?
Student Manual
Math Ready . Unit 8 . Lesson 5