Stem-and-leaf plots, step by step
A stem-and-leaf plot is a list of numbers stood on its side: the tens down the left, the ones along each row.
The question
How many values does the plot show?
How many values does the plot show?
1 | 5=15
15, 19, 20, 23, 23, 23, 27, 31, 34, 38, 42, 46
leaves:12
12
- Read the key before the data. Each leaf is a single DIGIT stuck onto its stem, so the 1 row with a 5 on it means 15 — not 1 and not 5. The row is a list of values, not a bar.
- That means the plot has kept every value, and kept them in order: 15, 19, 20, 23, 23, 23, 27, 31, 34, 38, 42, 46. Nothing has been rounded away and nothing has been grouped, which is what makes questions like this one answerable at all.
- Count the LEAVES, not the rows. There are 4 rows and 12 leaves altogether, and it is the leaves that are the values.
- So the answer is 12 minutes.
How it works.
- 01
Read the key before the data. Each leaf is a single DIGIT stuck onto its stem, so the 1 row with a 5 on it means 15 — not 1 and not 5. The row is a list of values, not a bar.
- 02
That means the plot has kept every value, and kept them in order: 15, 19, 20, 23, 23, 23, 27, 31, 34, 38, 42, 46. Nothing has been rounded away and nothing has been grouped, which is what makes questions like this one answerable at all.
- 03
Count the LEAVES, not the rows. There are 4 rows and 12 leaves altogether, and it is the leaves that are the values.
- 04
So the answer is 12 minutes.