ISASP High School Statistics and Probability. Practice it free.

Four data sets show the number of laps run in five trials. Which set has the least standard deviation?

Set A: $2, 4, 6, 8, 10$
Set B: $5, 5, 6, 6, 8$
Set C: $1, 5, 6, 7, 11$
Set D: $3, 5, 6, 7, 9$

Five afternoon temperatures, in degrees Fahrenheit, are $68\textsf{,}$ $72\textsf{,}$ $65\textsf{,}$ $74\textsf{,}$ and $71\textsf{.}$ Which data set has the same mean?

The distances, in miles, run on seven days are $14\textsf{,}$ $6\textsf{,}$ $20\textsf{,}$ $9\textsf{,}$ $11\textsf{,}$ $18\textsf{,}$ and $6\textsf{.}$ Which data set has the same median?

In three bowling games, Alex rolled scores of $142$, $156$, and $138$. In a fourth game, the score was $x$. The mean score over the four games is $150$. What is the value of $x$?

A box plot summarizes the data 2, 4, 5, 7, 9, 11, 13. Find the maximum.

A fundraiser uses a raffle drum divided into $3$ equal sections (A, B, and C) for ticket draws. After $900$ random draws, the counts were:

| Section | Draws |
| :-- | --: |
| A | $312$ |
| B | $255$ |
| C | $333$ |

The drum's pick-up opening favors some sections over others. Which change would most likely make the drum fair?

For a normal distribution, approximately what percent of data lies within 3 standard deviations of the mean? (Use the empirical rule; enter the number of percent.)

The mass of a chemical sample is modeled by $m(x)=480(0.92)^x$, where $x$ is the number of days after an initial measurement. According to the model, by what percent does the mass of the sample decrease each day?