Mean
How do you find the mean of a set of numbers?
You find the sum of your data values and divide by your number of data values.
True or false: the median and mode are always the same.
False. But they are often times very close.
What does mode mean?
What is range?
What is a dot plot for?
The purpose of a dot plot is to make sense of a large set of numbers.
What is the mean?
The average of the set of numbers.
How do you find the median?
You find the median by putting all of the data values in numerical order and finding the middle. If there are 2 middles, if there are an even number of data values, you find the average of these 2 numbers.
How do you find the mode on a dot plot?
What is frequency?
Frequency is how many times a number shows up in a set of numbers.
Explain how to create a dot plot.
Draw a number line, mark it with the numbers in a range. Mark a dot over each number in the range, one for every time that number occurs.
True or false: Mean is the most useful measure of central tendency.
False.
What is the median of a set of numbers?
The median is the middle of a set of numbers.
True or false: Mode is the most useful method of central tendency.
False.
How can you tell which is range and which is frequency?
On a dot plot, the range is the number line, while the frequency are the dots. On a chart, the top will be the range and the bottom the frequency. And in a set of numbers, the range is every number that shows up, while the frequency is how many times the numbers show up.
What does symmetrical mean in dot plots?
The dots are fairly evenly balanced on the left and right sides of the dot plot.
How can you find the mean of a set of numbers if you know the average, but one of the data values in missing?
You can take your average and multiply it by your number of data values. Then, you can find the sum of the data values that you do know, and subtract it from the number you found first.
How do you find the median on a dot plot?
You count your dots, find the middle number, count to that middle number, and see where it falls on your range.
How do you find the mode in a large set of numbers?
You see which one comes up the most.
Should you include a number on a range if that number does not show up in a data set, yet it fall withing numbers that do show up?
For example: if students score between 6-10, but no one gets a 7, do I include it on my range?
Yes!
What does skewed mean? How are skews named?
If the "tail" or lower end of the dots is on the right, the plot is right-skewed, if the tail is on the left, it is left skewed.
13 students take a quiz. Here are their scores:
Score: 6 7 8 9 10
Kids: 2 3 5 2 1
Find the average score on the quiz.
Total scores: 101
Number of students: 13
101/ 13= 7.76
Can there by more than one median?
No.
Can there be more then one mode?
Yes, as long as every number does not appear the same number of times, there is a mode.
RANDOM CHALLENGE
What is the average age of students in the class?
When you describe a dot plot, what should you include?
The range, the peak and whether it is symmetrical or skewed. If it's skewed, say whether it's left or right-skewed.