PSLE Perry had blue pens and orange pens for sale. He sold 150 blue pens. 40% of the pens sold were orange.
- How many blue pens and orange pens did Perry sell altogether?
- He sold 50% of his pens. 80% of the pens left unsold were blue. How many orange pens did Perry have at first?
|
Blue |
Orange |
Total |
Total in percent |
Before |
7 u |
3 u |
10 u |
100% |
Change |
- 60% - 3 u |
- 40% - 2 u |
- 100% - 5 u |
- 50% |
After |
80% 4 u |
20% 1 u |
100% 5 u |
50%
|
40% =
40100 =
25 Total number of pens sold = 5 u
Number of orange pens sold = 2 u
Number of blue pens sold
= 5 u - 2 u
= 3 u
3 u = 150
1 u = 150 ÷ 3 = 50
Total number of pens sold
= 5 u
= 5 x 50
= 250
(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 blue = 80%
Percent of the pens left unsold that were orange = 100% - 80% = 20%
Number of the pens left unsold that were orange
= 20% x 5 u
=
20100 x 5 u
= 1 u
Number of orange pens that Perry had at first
= 1 u + 2 u
= 3 u
= 3 x 50
= 150
Answer(s): (a) 250; (b) 150