Aussie Maths & Science Teachers: Save your time with SmarterEd
The heights of 400 students were measured. The results are displayed in this cumulative frequency polygon.
Use the polygon to estimate the interquartile range. (2 marks)
--- 4 WORK AREA LINES (style=lined) ---
`text(See graph for values:)`
| `IQR` | `= Q_3 – Q_1` |
| `= 172 – 136` | |
| `= 36\ text(cm)` |
The heights of the 60 members of a choir were recorded. These results were grouped and then displayed as a cumulative frequency histogram and polygon.
The shortest person in the choir is 140 cm and the tallest is 190 cm.
Draw an accurate box-and-whisker plot to represent the data. (3 marks)
--- 8 WORK AREA LINES (style=lined) ---
`text(Low) = 140`
`text(High) = 190`
`text(Median) = 150\ \ \ \ text{(# People = 30)}`
`Q_1 = 145\ \ \ \ text{(# People = 15)}`
`Q_3 = 170\ \ \ \ text{(# People = 45)}`
`text(Box and Whisker)`
A set of data is represented by the cumulative frequency histogram and ogive.
What is the best approximation for the interquartile range for this set of data?
| `IQR` | `= Q3 − Q1` |
| `= 80 − 45` | |
| `= 35` |
`=> C`