PSLE Bobby had purple markers and red markers for sale. He sold 180 purple markers. 40% of the markers sold were red.
- How many purple markers and red markers did Bobby sell altogether?
- He sold 50% of his markers. 70% of the markers left unsold were purple. How many red markers did Bobby have at first?
| |
Purple |
Red |
Total |
Total in percent |
| Before |
6.5 u |
3.5 u |
10 u |
100% |
| Change |
- 60%
- 3 u |
- 40%
- 2 u |
- 100%
- 5 u |
- 50% |
| After |
70%
3.5 u |
30%
1.5 u |
100%
5 u |
50%
|
40% =
40100 =
25 Total number of markers sold = 5 u
Number of red markers sold = 2 u
Number of purple markers sold
= 5 u - 2 u
= 3 u
3 u = 180
1 u = 180 ÷ 3 = 60
Total number of markers sold
= 5 u
= 5 x 60
= 300
(b)
Percent of the markers left unsold = 100% - 50% = 50% 50% of the markers that were sold = 5 u 50% of the markers that were left unsold = 5 u Percent of the markers left unsold that were purple = 70%
Percent of the markers left unsold that were red = 100% - 70% = 30%
Number of the markers left unsold that were red
= 30% x 5 u
=
30100 x 5 u
= 1.5 u
Number of red markers that Bobby had at first
= 1.5 u + 2 u
= 3.5 u
= 3.5 x 60
= 210
Answer(s): (a) 300; (b) 210
