Page 193 - MAT KS3 Y8 Cambridge CheckPoint

End-of-unit review

End-of-unit review
20 Mass of items posted by an internet
company in one week
1 The frequency diagram shows the masses of the items
posted by an internet company in one week. 16
a Why are there no gaps between the bars of this
frequency diagram? Frequency 12
b How many items weighed 600–800 g? 8
c What was the most common mass of items posted?
d How many more items were posted that weighed
4
0–200 g than 200–400 g?
e How many items were posted altogether?
0 200 400 600 800 1000
Mass (g)
2 The frequency table shows the number of MP3 players
Gio sold each day in his shop during one month. Number of MP3 players sold Frequency
a Draw a frequency diagram to show the data.
b Can you tell which month your frequency 0–9 3
diagram represents? Explain your answer. 10–19 5
c Gio says: ‘The frequency diagram shows that that 20–29 12
the highest number of of MP3 players sold in one 30–39 8
day was less than 50.’ 40–49 2
Is Gio correct? Explain your answer.
d Draw a pie chart to represent the data.
e On what percentage of days in the month were between 20 and 29 MP3 players sold?

3 The students in class 8T took a test. These are the results, marked out of 50.

28 12 50 28 24 39 46 27 18 50 49 28 36
45 34 43 8 28 36 37 18 39 29 38 9

a Draw an ordered stem-and-leaf diagram showing their scores out of 50.
b What percentage of the students had a score greater than 35?
c What fraction of the students had a score less than 25?
d Any student scoring less than 40% must re-sit the test.
How many students do not have to re-sit the test?
e Read what Zalika says.

I had the average score, because my
mark was 28 out of 50.

i Show that Zalika could be correct.
ii Show that Zalika could be wrong.

18 Interpreting and discussing results 191