7th 6-4 More Comparative Inferences

The education board is analyzing the amount of time students spend on homework each night. They take a random sample of 10 students from each school. Which measure of center should the education board use to analyze the​ data?

• Median

• Mean

• IQR

• MAD

The education board is analyzing the amount of time students spend on homework each night. They take a random sample of 10 students from each school. What can you infer using the measure of​ center?

• You can infer from the means that the students of School X spend the same amount of time on homework than the students of School Y.

• You can infer from the IQRs that the amount of time students spend on homework is fairly consistent within each school.

• You can infer from the IQRs that the amount of time students spend on homework varies significantly within each school.

• You can infer from the medians that the students of School X spend less time on homework than the students of School Y.

There are two types of plants in a greenhouse. The following dot plots show the heights of 20​ plants, 10 of Type 1 and 10 of Type 2. The plants are given the same amount of food and water and grow at the same rate. What is the mean height for Type 1?

• 41

• 42

• 43

• 44

There are two types of plants in a greenhouse. The following dot plots show the heights of 20​ plants, 10 of Type 1 and 10 of Type 2. The plants are given the same amount of food and water and grow at the same rate. What is the mean height for Type 2?

• 38

• 39

• 40

• 41

There are two types of plants in a greenhouse. The following dot plots show the heights of 20​ plants, 10 of Type 1 and 10 of Type 2. The plants are given the same amount of food and water and grow at the same rate. What is an inference that can be made from the means?

• Type 2 is typically taller.

• Type 1 is typically taller.

• The types are typically the same height.

There are two types of plants in a greenhouse. The following dot plots show the heights of 20​ plants, 10 of Type 1 and 10 of Type 2. The plants are given the same amount of food and water and grow at the same rate. Why you would want to use a dot plot to find the mean instead of a box plot.

• Box plots give you the mean.

• Box plots contain all the data in the data set.

• Dot plots contain all the data in the data set.

• Dot plots give you the mean.

The following dot plots show the ages of two groups of tourists. Make a comparative inference based on the mean values. What is the first step for calculating the mean?

• The first step should be to count the ages that have dots and just average those numbers.

• The first step should be to find the middle number of all the dots.

• The first step should be to count the number of dots for each age.

• The first step should be to average the minimum and maximum values that have dots.

The following dot plots show the ages of two groups of tourists. Make a comparative inference based on the mean values. The mean for group 1 is?

• 41

• 41.5

• 42

• 42.5

The following dot plots show the ages of two groups of tourists. Make a comparative inference based on the mean values. The mean for group 2 is?

• 46.5

• 47

• 47.5

• 48

Juanita recorded samples of the lengths of the shadows cast by elm trees in two of her​ neighbors' yards at the same time of day. The median of the sample from Neighbor​ X's yard is 20 feet. The median of the sample from Neighbor​ Y's yard is 50 feet. Which is a comparative inference that Juanita can make from the median​ values?

• Most of the elm trees in Neighbor​ Y's yard are older than the elm trees in Neighbor​ X's yard.

• There are more elm trees in Neighbor​ Y's yard than in Neighbor​ X's yard.

• Most of the elm trees in Neighbor​ X's yard are older than the elm trees in Neighbor​ Y's yard.

• There are more elm trees in Neighbor​ X's yard than in Neighbor​ Y's yard.