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Chapter 10: Q. 10.12 (page 588)

A new prep class was designed to improve SAT test scores. Five students were selected at random. Their scores on two practice exams were recorded, one before the class and one after. The data recorded in the table given below. Are the scores, on average, higher after the class? Test at a 5%level.

Short Answer

Expert verified

No sufficient evidence is obtained to conclude that the class improves SAT scores significantly at a level of 5%.

Step by step solution

01

Given information

Give the scores on two practice tests of five students, one before and after the class.

02

Calculation

The null and alternative hypothesis is

H0:μd=0Ha:μd>0

The significant level, α=5%=0.05.

p-value=0.0874

The p-value>0.05, therefore we do not reject the null hypothesis. As a result, there is insufficient data to infer that the class significantly increases SAT scores at 5%significant level.

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Most popular questions from this chapter

Use the following information to answer the next five exercises. A doctor wants to know if a blood pressure medication is effective. Six subjects have their blood pressures recorded. After twelve weeks on the medication, the same six subjects have their blood pressure recorded again. For this test, only systolic pressure is of concern. Test at the 1%significance level.

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____________.
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