PSLE The bar graph shows the number of pens sold from Jul to Sep. The number of pens sold is not shown on the scale.
- What was the percentage increase in the number of pens sold from Aug to Sep?
- There were 30 more pens sold in Jul than in Aug. How many pens were sold in Sep?
- The average number of pens sold from Jul to Nov was 112. What was the average number of pens sold in Oct and Nov?
(a)
Percentage increase in the number of pens sold from Aug to Sep
=
8 - 22 x 100%
=
62 x 100%
= 300%
(b)
Difference in intervals between Jul and Aug
= 5 - 2
= 3
3 intervals → 30
1 interval → 30 ÷ 3 = 10
Number of pens sold in Sep
= 8 intervals
= 8 x 10
= 80
(c)
Total intervals from Jul to Sep
= 5 + 2 + 8
= 15
Total number of pens sold from Jul to Sep
= 15 intervals
= 15 x 10
= 150
Total number of pens sold from Jul to Nov
= 5 x 112
= 560
Number of pens sold from Oct to Nov
= 560 - 150
= 410
Average number of pens sold in Oct and Nov
= 410 ÷ 2
= 205
Answer(s): (a) 300%; (b) 80; (c) 205