PSLE Michael had pink pens and yellow pens for sale. He sold 120 pink pens. 40% of the pens sold were yellow.
- How many pink pens and yellow pens did Michael sell altogether?
- He sold 50% of his pens. 70% of the pens left unsold were pink. How many yellow pens did Michael have at first?
| |
Pink |
Yellow |
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 pens sold = 5 u
Number of yellow pens sold = 2 u
Number of pink pens sold
= 5 u - 2 u
= 3 u
3 u = 120
1 u = 120 ÷ 3 = 40
Total number of pens sold
= 5 u
= 5 x 40
= 200
(b)
Percent of the pens left unsold = 100% - 50% = 50% 50% of the pens that were sold = 5 u 50% of the pens that were left unsold = 5 u Percent of the pens left unsold that were pink = 70%
Percent of the pens left unsold that were yellow = 100% - 70% = 30%
Number of the pens left unsold that were yellow
= 30% x 5 u
=
30100 x 5 u
= 1.5 u
Number of yellow pens that Michael had at first
= 1.5 u + 2 u
= 3.5 u
= 3.5 x 40
= 140
Answer(s): (a) 200; (b) 140
