Step by step
The question
Question: make a stem-and-leaf plot of 56, 72, 64, 81, 59, 67, 75, 62, 70 and 68.
Find the median.
1 Split the numbers
The tens digit is the stem.
The ones digit is the leaf.
56: stem 5, leaf 6.
Careful!
Every plot needs a key.
5, line, 6 means 56, not 11.
2 Write the leaves
The stems go down the side: 5, 6, 7 and 8.
56: leaf 6 goes after stem 5.
We cross out 56.
72: leaf 2 after stem 7.
And so on, in the order they come.
3 Put the leaves in order
Now we write the plot again, with each row of leaves in order, smallest first.
Stem 5: 6 and 9.
And the key: 5, line, 6 means 56.
4 Read the plot
The leaves are in order now.
We cross out the smallest and the biggest.
And the next pair, and so on.
Two are left in the middle: 67 and 68.
The median is halfway between them.
Halfway: we add them and divide by 2.
67 plus 68 is 135.
Divided by 2 is 67.5.
So the median is 67.5.
5 Check
Let's check: the plot has 10 leaves, one for each of the 10 numbers.
So none is lost!
Let's look back.
First: split the numbers.
Then: write the leaves.
Then: put the leaves in order.
Then: read the plot.
Last: check.