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Chapter 10: Q. 41 (page 666)

How many pairs of shoes do teenagers have? To find out, a group of AP庐 Statistics students conducted a survey. They selected a random sample of 20female students and a separate random sample of 20male students from their school. Then they recorded the number of pairs of shoes that each student reported having. Here are their data:

Let 渭1=the true mean number of pairs of shoes that male students at the school have and 渭2=the true mean number of pairs of shoes that female students at the school have. Check if the conditions for calculating a confidence interval for 渭1-渭1are met.

Short Answer

Expert verified

Females and males groups have 30.5and 11.6pairs of shoes respectively.

Step by step solution

01

Step 1. Given information

Given:

02

Step 2. Concept used

The Mean formula: x炉=鈭�Xn

where,

Sum of all data values:鈭�X

Number of data values: n

03

Step 3. Calculation

Let鈥檚 take given table and find out its sum first:

Now, the pairs of shoes having by teenagers is calculated by calculating the mean:

X炉M=鈭�232n=23220=11.6X炉F=鈭�607n=23220=30.5

Hence, females and males groups have 30.5and 11.6pairs of shoes respectively.

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