Dot Plots and Histograms

The shape of a distribution.

12 problems · about 21 minutes · TEKS P.S.1.B, S-ID.A.1

NameDate

Figure — use these to answer the problems

Change the counts to build a shape. Pile the marks on the left and stretch a tail right for a skewed-right distribution.

123456

Number of pets

1 pet6

2 pets5

3 pets3

4 pets1

5 pets0

6 pets1

Figure 1

Straightforward practice. Get the method working first.

5 problems

Counts 9, 4, 2, 1. Skewed which way? 1 right, 2 left.
Answer
2
Why does bin width matter in a histogram?
- The same data can appear to have a different shape under different widths.
- It changes the colour of the bars.
Counts 2, 4, 6, 4, 2. Symmetric or skewed? 1 symmetric, 2 skewed.
Answer
Counts 8, 5, 2, 1, 1. Skewed which way? 1 right, 2 left.
Answer
Counts 1, 1, 2, 5, 8. Skewed which way? 1 right, 2 left.
Answer

The same ideas with more to keep track of.

3 problems

Counts 3, 3, 4, 2. How many values in total?
Answer
A histogram of 100 values uses 2 bins. Is the shape well shown? 1 for yes, 0 for no.
Answer
Counts 5, 1, 0, 1, 5. How many peaks?
Answer

Mixed problems. Work out what kind of question it is before you start.

4 problems

9
Which are good reasons to investigate an outlier rather than delete it?
- It may be the most interesting value in the set
- It may reveal a recording error worth fixing
- It makes the graph look untidy
- It lowers the average
- Tick every box that applies.
Counts 1, 2, 7, 2, 1. Symmetric or skewed? 1 symmetric, 2 skewed.
Answer
The Tail
A distribution has most data on the left and a long tail to the right. Is it skewed right or left? 1 right, 2 left.
Answer
The Count
A dot plot shows 6, 5, 3, 1, 0 and 1 marks above the values 1 to 6. How many students in total?
Answer