How to find mean

Question

21 15 19 16 17 17 18 20 25 7 16 10 16 18 12 find mean, mode, and median

 

Answer 1

All right, for this problem you must know the differences between mean, mode, and median.

 

Let's start with "mean". Mean is another word for average, which is found by taking all of the numbers and dividing by how many numbers were added together. In this case, there are fifteen numbers so you would divide the sum of numbers by 15. All of the numbers added together equal 247 (21+15+19+16+...+18+12=247) so the mean is 247/15 which is 16.4667 or 16.467.

 

To find the next two amounts, mode and median, it helps if the numbers are listed in numerical order listing repeat numbers. So before anything else, let's arrange the numbers as such: 7, 10, 12, 15, 16, 16, 16, 17, 17, 18, 18, 19, 20, 21, 25.

 

The "mode" is the number that appears the most often, or in other words the number that has been repeated the most number of times. You can have more than one mode, but in this case the mode is 16 since there are three of them while no other number is repeated as many times.

 

The "median" is found by finding the number that lies in the middle of the sequence. This can be done by crossing off the numbers from both ends, working your way towards the middle. Doing that for this problem gives you 17 as the answer: 7, 10, 12, 15, 16, 16, 16, 17, 17, 18, 18, 19, 20, 21, 25.

 

So, the mean is 16.467 when rounded, the mode is 16, and the median is 17.

Answer 2

Hi Az.

 

To find the mean you add all the numbers and divide by the number of numbers. So adding them together you get 247. There are 15 numbers. 247/15 = 16.5

 

To find the median, you list all the numbers in numerical order and the median is the middle one. If there are 2 middle numbers then you average the two of them and that is the median.

So: 7, 10, 12, 15, 16, 16, 16, 17, 17, 18, 18, 19, 20, 21, 25. Cross off 7 numbers from the left and from the right which leaves a middle number of 17. So the median is 17. (It's a good idea to count the numbers in your ordered list to make sure you didn't miss any. Here there are 15 numbers which is the number of numbers.)

 

The mode is the number that occurs most often - or if there is a tie, then there is more than one mode. Here 16 occurs 3 times and that is the most times any number occurs. So the mode is 16.

 

Hope this helps.

 

Sincerely,

Diana R.

Answer 3

mean: add the numbers together and divide by the number of numbers

the sum of the numbers is 247

247/15=16.4666... is the mean (round accordingly)

mode: the most frequently occurring number which is 16 which occurs 3 times

median: the number in the middle when there is an odd number of numbers and the numbers have been arranged according to size, smallest to largest or largest to smallest; if there is an even number of numbers, the median is the mean of the 2 middle numbers after arranging the numbers according to size

7, 10, 12, 15, 16, 16, 16, 17, 17, 18, 18, 19, 20, 21, 25

the middle number is the eighth number which is 17; the median is 17