7 Doing homework A school newspaper article claims
that 60% of the students at a large high school did all
their assigned homework last week. Some skeptical
AP Statistics students want to investigate whether this
claim is true, so they choose an SRS of 100 students
from the school to interview. What values of the sample
proportion p would be consistent with the claim that
the population proportion of students who completed
all their homework is p = 0.60? To find out, we used
Fathom software to simulate choosing 250 SRSs of size
n = 100 students from a population in which p = 0.60.
The figure below is a dotplot of the sample proportion
of students who did all their homework.


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00000000000
00000

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000000
QO
O
0.45
0.50
0.55 0.60 0.65 0.70 0.75
proportion_yes
(a) There is one dot on the graph at 0.73. Explain what
this value represents.
(b) Describe the distribution. Are there any obvious outliers?
(c) Would it be surprising to get a sample proportion of
0.45 or lower in an SRS of size 100 when p = 0.6?
Justify your answer.
(d) Suppose that 45 of the 100 students in the actual
sample say that they did all their homework last
week. What would you conclude about the newspa-
per article's claim? Explain.