Look at this set of 10 numbers:

1 7 3 9 9 9 5 9 4 5

By how much would the median decrease if the number 6 were added to the set?

The median is the middle number of all the numbers in the data set which are in numerical order.

1st put them in numerical order and close one off from each end until you get to the middle

1 3 4 5 5 7 9 9 9 9

Because there is an even number, there are two numbers so you have to take the average.

(5+7) / 2 = 6

For the new number group, add 6 to the list

1 3 4 5 5 6 7 9 9 9 9

Cross one off from each side until you get the middle and the new median is also 6.

Therefore, the median did not decrease, it stayed the same.

In the original set of numbers, the median is six

But, if six was added to the set, then the median would be six

So the median wouldn't decrease at all