Page 416 - Math Smart - 7

Rainfall In Hyderabad
Which chart is better?
I Jan
For each statement, tick the
box indicating where the I Feb
information can be found.
Mar
The month during which
Apr
the highest rainfall was
May
received.
Bar chart □ Pie chart □ Jun
I Jul
The amount of rainfall
received in May. i Aug
Bar chart Q Pie chart □ Sep

The difference in the Get
amount of rainfall received Nov
in April and December.
Dec
Bar chart Q Pie chart Q
The month that received Bar charts show changes over time Pie charts show comparisons between
20 mm of rainfall. more effectively than pie charts. parts of a whole more effectively than
Bar chart Q Pie chart □ Bar charts are useful when specific bar charts. They do not show changes
The trend in rainfall values are required, for example overtime.
received from January to rainfall in millimetres. Pie charts are useful when we want
August. to compare one amount to another in
Bar chart □ Pie chart □ the data set.
Revision
O Journal Writing O Chichi took 7 Mathematics tests. What is the range of her test scores?

Using the data you 87, 75, 86, 93, 89, 78, 94
collected for the survey
conducted in Unit 7, Look at the data below.
select a suitable type 19, 25, 59, 48,35,31,30, 32,51
of chart to present a) Find the range.
your data.
b) Find the mode.
explain why you chose c) Calculate the mean. Round your answer to the nearest 1 d.p.
this type of chart,
d) Find the median.
present your data in
a separate chart for e) Find the new median if 25 is replaced by 52 and 19 is replaced by 29.
each class or group. f) Find the new mean if 25 is replaced by 52 and 19 is replaced by 29.
compare the charts to Round your answer to the nearest 1 d.p.
draw a conclusion that
supports or rejects Q List a set of 5 different numbers where the mean is the same as the median.
your hypothesis. O List a different set of 4 different numbers where the mean is the same as

the mode.
e The data set below is the test scores (out of ICQ) for a Maths test for 20 pupils.
56, 29, 78, 67, 68, 69, 80, 89, 92, 71, 58, 66, 56, 88, 81, 70, 73, 63, 74, 38
a) Construct a tally and frequency table for this data set. Decide what class

intervals would be suitable.
^12 UNIT 17 Data Handiin
I