6.1 6.3 Distribution of Sample Proportions
Central Limit Theorem for Proportions
The distribution of a sample proportion is
approximated by a normal distribution with
mean = p and SE = !

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CONFIDENCE INTERVALS
When we take a sample and
calculate the mean of a
sample it will be used to
estimate
the
population
parameter.
CONFIDENCE INTERVALS
In order to determine the number o

Proportion and Confidence Interval Problems
1.
Government data show that 10% of males under age 25 are
unemployed. A random sample is taken of 400 males who are in
the labor force and under age 25. Find the probability that the
sample unemployment rate is

Math 4 Confidence Intervals of Sample Proportions
Name_
The cure rate for the standard treatment of a disease is 45%. Dr. Snyder has perfected a primitive treatment which
he claims is much better. As evidence, he says that he has used his new treatment on

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Confidence Intervals
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Accelerated Mathematics III Study Guide
Fall 2011 District-wide Semester Exam
Henry County Schools
IN ADDITION TO THESE SAMPLE PROBLEMS, STUDENTS SHOULD REVIEW ALL PREVIOUS TEST
QUESTIONS, CLASS NOTES, AND FORMATIVE ASSESSMENTS, ETC IN PREPARATION FOR THI

Proportion and Confidence Interval Problems
Answers
1.
Government data show that 10% of males under age 25 are unemployed. A
random sample is taken of 400 males who are in the labor force and under
age 25. Find the probability that the sample unemployment