Question

The weights (in ounces) of 18 cookies are shown.
0.71    1.35    0.85    1.62    0.75    0.87   
1.35    1.53    0.99    0.71    1.19    1.47   
0.47    1.22    0.87    1.47    1.72    0.75

Find the IQR of the given sample data. Show the exact value, no rounding.

Answer:

2.

The amount spent on textbooks for the fall term was recorded for a sample of five hundred university students. The mean expenditure was calculated to be $500 and the median expenditure was calculated to be $425. Which of the following statements is accurate?

Select one:

The most frequently occurring textbook cost in the sample was $425

50% of the students sampled had textbook costs that were no less than $425

50% of the students sampled had textbook costs that were less than $500

50% of the students sampled had textbook costs equal to $425

50% of the students sampled had textbook costs equal to $500

3.

Suppose the results of a math test given to a group of 30 students can be summarized as follows: the mean of the test scores is 78, and the median of the test scores is 71. What type of distribution most likely describes the shape of the test scores?

Select one:

symmetric

skewed to the right

unable to determine with the information given

skewed to the left

Answer 1

1). arranging the data in ascending order:-

0.47,0.71,0.71,0.75,0.75,0.85,0.87,0.87,0.99,1.19,1.22,1.35,1.35,1.47,1.47,1.53,1.62,1.72

here, number of observations(N) = 18

the first quartile be:-

[ 4 th obs = 0.75, 5 th obs=0.75 ]

the third quartile be:-

[ 14 th obs = 1.47, 15 th obs=1.47 ]

the interquartile range be:-

=third quartile - first quartile

= ( 1.47 - 0.75)

= 0.72

2).the following statements which is accurate be:-

50% of the students sampled had textbook costs that were no less than $500.

[ as median indicates that  50% of the data values are less than or equal to the median value.so, we can say that 50% of the data values are not less than the median value.]

3). the type of distribution that is most likely to describe the shape of the test scores:-

skewed to the right

[ mean = 78, median = 71

mean > median.

so, this is positively skewed distribution.]

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