The two dot plots below show the heights of some sixth graders and some seventh graders: The mean absolute deviation (MAD) for the first set of data is 1.2 and the MAD for the second set of data is 1.7. Approximately how many times the variability in the heights of the sixth graders is the variability in the heights of the seventh graders? (Round all values to the tenths place.)

1.2
1.4
2.4
2.8

If y varies directly as x2 and y=6 when x=6, find the constant of variation.

Titus works at a hotel. part of his job is to keep the complimentary pitcher of water at least half full and always with ice. when he starts his shift, the water level shows 4 gallons, or 128 cups of water. as the shift progresses, he records the level of the water every 10 minutes. after 2 hours, he uses a regression calculator to compute an equation for the decrease in water. his equation is w –0.414t + 129.549, where t is the number of minutes and w is the level of water. according to the equation, after about how many minutes would the water level be less than or equal to 64 cups?

Arandomized controlled trial is designed to evaluate the effect of metoprolol in patients with heart failure. while preparing for statistical analysis, the researcher reviews some common types of statistical errors. which of the following statements is true regarding a type i error in a clinical study? a. the study is not significantly powered to detect a true difference between study groups. bthe null hypothesis is true but is rejected in error. c. the null hypothesis is false but is accepted in error. d. type i error is also known as beta and is usually 0.1 or 0.2. e. type i error depends on the study's confidence interval.