Astudent researcher conducts an experiment that investigates the effects of
a new mathematics website on student achievement. she randomly assigns
students to two groups: one that receives supplemental instruction from the
website and one that doesn't receive the supplemental instruction. each
sample consists of 20 students. observations of student engagement are
rated by the researcher, according to an engagement scale. how could this
study be improved?
select all that apply.

a. increase the sample size.

b. have another researcher provide ratings, as well.

c. limit observations to students who are engaged.

d. administer a quiz or exam that gauges student understanding.

Draw a tape diagram to represent each situation. for some of the situations, you need to decide what to represent with a variable andre bakes 9 pans of brownies. he donates 7 pans to the school bake sale and keeps the rest to divide equally among his class of 30 students

Create a question with this scenario you could ask that could be answered only by graphing or using logarithm. david estimated he had about 20 fish in his pond. a year later, there were about 1.5 times as many fish. the year after that, the number of fish increased by a factor of 1.5 again. the number of fish is modeled by f(x)=20(1.5)^x.

Name and describe the three most important measures of central tendency. choose the correct answer below. a. the mean, sample size, and mode are the most important measures of central tendency. the mean of a data set is the sum of the observations divided by the middle value in its ordered list. the sample size of a data set is the number of observations. the mode of a data set is its highest value in its ordered list. b. the sample size, median, and mode are the most important measures of central tendency. the sample size of a data set is the difference between the highest value and lowest value in its ordered list. the median of a data set is its most frequently occurring value. the mode of a data set is sum of the observations divided by the number of observations. c. the mean, median, and mode are the most important measures of central tendency. the mean of a data set is the product of the observations divided by the number of observations. the median of a data set is the lowest value in its ordered list. the mode of a data set is its least frequently occurring value. d. the mean, median, and mode are the most important measures of central tendency. the mean of a data set is its arithmetic average. the median of a data set is the middle value in its ordered list. the mode of a data set is its most frequently occurring value.