PSLE The bar graph shows the number of notebooks sold from Jul to Sep. The number of notebooks sold is not shown on the scale.
- What was the percentage increase in the number of notebooks sold from Jul to Aug?
- There were 88 less notebooks sold in Jul than in Sep. How many notebooks were sold in Jul?
- The average number of notebooks sold from Jul to Nov was 167. What was the average number of notebooks sold in Oct and Nov?
(a)
Percentage increase in the number of notebooks from Jul to Aug
=
5 - 22 x 100%
=
32 x 100%
= 150%
(b)
Difference in intervals between Sep and Jul
= 10 - 2
= 8
8 intervals → 88
1 interval → 88 ÷ 8 = 11
Number of notebooks sold in Jul
= 2 intervals
= 2 x 11
= 22
(c)
Total intervals from Jul to Sep
= 2 + 5 + 10
= 17
Total number of notebooks sold from Jul to Sep
= 17 intervals
= 17 x 11
= 187
Total number of notebooks sold from Jul to Nov
= 5 x 167
= 835
Number of notebooks sold from Oct to Nov
= 835 - 187
= 648
Average number of notebooks sold in Oct and Nov
= 648 ÷ 2
= 324
Answer(s): (a) 150%; (b) 22; (c) 324