Math CC7/8 – May 1
Things Needed Today (TNT):
Pencil/Math Notebook/Calculators/book
TwMM 4.2
Math Notebook:
1.Topic: Negative Correlation
2.HW: p. 98 #4-5, #17-18
What’s Happening Today?
•Finish Scatter Plot Foldable
•Lesson 4.2– Negative
Correlation
The graph shows the data from the table and a line that models the data.
Questions to Think About
 How would you describe
the relationship between
age & race time?
 Would you say the
relationship is strong or
weak?
 Are the data points close
to the line or spread out?
 From the scatter plot, how do you know if a
linear model fits the data?
 How do you know if there are outliers?
 How do you know if the relationship is
negative or positive?
About -5 = -1.25
4
It is a negative slope,
so as age increases by
one year, race time
decreases by 1.25
seconds
There is a reasonable linear
trend, so we could probably
predict a race time of close to
20 seconds.
Hmmm…
 Beyond 18 or so, running speed doesn’t
increase much.
 Also, the rate of increase might slow
since this data would predict a time of 6
or 7 seconds for age 20 – that’s better
than the world record!
Answers vary…
(10, 20) and (13, 17) don’t
seem to fit the model.
These indicate a slower
than expected running speed
– race time is longer than
predicted by the trend line.
Answers vary…
No…
The point for this player would lie above the line s = h
because his arm span is greater than his height.
1. Are age and GPA strongly related for
these students? Explain.
No, the scatter plot does not show a strong relationship
between these variables - the scatter is NOT clustered
along a line.
2. How is your answer supported by
the table? By the scatter plot?
Table – high and low GPAs, all ages
Graph – No linear trend