Measures of Central Tendency

Question 1

What are the three measures of central tendency?

Answer 1

• Mean
• Median
• Mode

Question 2

What does the median tell us?

Answer 2

It splits the data in half. This means 50% of the data is below the median and 50% is above it.

Question 3

What does the mode tell us?

Answer 3

It tells us the most common answer. It’s the number (or category) that is listed most often.

Question 4

How do you find the median of a list of data?

Answer 4

1. Count how many data there are. Add 1. Divide that by 2.
2. Starting from the bottom, count up however much you just calculated in step 1.
   (If this is a decimal, the median is in between two numbers. You need to average these two numbers to find the median.)

Question 5

How do you calculate mean from a frequency table?

Answer 5

GET MAD!!

1. Multiply value and frequency.
2. Add up all the new values and all the frequencies.
3. Divide the totals.

Question 8

How do you find the median from a frequency table?

Answer 8

1. Find the cumulative frequency.
2. Identify the closest bigger number to half of the frequency.
3. Median is the value in the 1st column.

Question 9

How do you find the mean of a list of data?

Answer 9

You add up all of the values and then divide by the number of values there are.

Question 10

What is the math word we mean when we say “average” or “on average”?

Answer 10

MEAN

Question 11

What is the fancy math communication sentence that we should use when talking about mean?

For example, the mean for number of texts per day sent by teenagers = 8.6.

Answer 11

• “On average, teens send 8.6 text messages per day.”
• “The average teen sends 8.6 text messages per day.”
• “The average number of text sent by teens per day is 8.6.”