I
8-13.
Mrs. Ferguson, your school librarian, asks you to
conduct a suryey of how many books students read
during the year. You get the following results: 12,24,
10,32, 12, 4,35, 10, 8, 12, 15,20, 18,25,21, and 9.
(J
:l)
o-
C)
!
a.
b.
t!
Use the data to create a histograrn. Use a bin width
010203040
of l0 books. I See histogram at right. ]
Number ol Books Read
Is the rlean or median a better measure of the center? Find the value of
whichever is more appropriate. I The data is nearly symmptric lvith no
outliers so either mean or median are appropriate. Mean = L6.69 books,
median = 13.5 books l
Make a box plot of the clata. I See box plot at right. ]
d.
Describe the center, shape, spread, and outliers of the
distribution. I The typical student reads about 13.5
books; the distribution is nearly symmetrical and
single-peaked; some students may say there is a
slight right skerv, apparent in the box plot; the IQR is 12.5 so there is a lot of
variability in the number of books read; there are no apparent outliers. I
Core Conttectiotts. Ccttrse 2
836
8- r4.
Copy and complete each of the Diamond Problems below.
The pattern used in the Diamoltd Problems is shown at right.
I See anslvers in bold in the diamonds below. ]
d.
8-1s.
Solve the following equations using any method. Show your work and check your
solution.
a. 5x+2A=3x*4
I x=-8 ]
b. 7x-4:3x*8
t x:3 l
c. 2x+6=x-9
I x=-15 ]
8-16.
(
8- 17.
8-r8.
Mariana ancl Felix were in science class and were using a test kit to measure the
amount of calcium in milk. They measured the amount of calcium in I cup of milk
10 times ancl got a mean of 294.6 mg. They looked up the amount of calcium that is
typically in milk anclfound out it was 290 mg per 1 cup. Percent error finds the
difference between the actual value and measured valtte and the compares tliat
difference to the actual value as a percentage. Find the percent error of Mariatla and
Felix's Ineasurement. lL.6Vo l
If five so,lgs can be clownloacled for $6, what is the cost of seven songs? t $S.+O
1
Roger has a bag of marbles. There are 6 red,4 blue, 3 white, andT green marbles irt
the 6ag. If he draws one marble, replaces it, and then draws another, find the
following probabilities. Write yotlr answer as a fraction and a percent.
a.
t
P(red, red)
9Vo
=
t'+ *'=
cl.
b.
l
I
P(not white, green)
= **fi = 29.75Vo l
*.t
c. P(blue or white, red)
t +'+ = #' = 10'5vo l
Find tlie answer for part (a) above if Roger does ttot replace the marble before
selecting the second one. [ *'fr = irt = 7 .99o ]