PSLE Julian had green pens and blue pens for sale. He sold 300 green pens. 70% of the pens sold were blue.
- How many green pens and blue pens did Julian sell altogether?
- He sold 50% of his pens. 75% of the pens left unsold were green. How many blue pens did Julian have at first?
|
Green |
Blue |
Total |
Total in percent |
Before |
10.5 u |
9.5 u |
20 u |
100% |
Change |
- 30% - 3 u |
- 70% - 7 u |
- 100% - 10 u |
- 50% |
After |
75% 7.5 u |
25% 2.5 u |
100% 10 u |
50%
|
70% =
70100 =
710 Total number of pens sold = 10 u
Number of blue pens sold = 7 u
Number of green pens sold
= 10 u - 7 u
= 3 u
3 u = 300
1 u = 300 ÷ 3 = 100
Total number of pens sold
= 10 u
= 10 x 100
= 1000
(b)
Percent of the pens left unsold = 100% - 50% = 50% 50% of the pens that were sold = 10 u 50% of the pens that were left unsold = 10 u Percent of the pens left unsold that were green = 75%
Percent of the pens left unsold that were blue = 100% - 75% = 25%
Number of the pens left unsold that were blue
= 25% x 10 u
=
25100 x 10 u
= 2.5 u
Number of blue pens that Julian had at first
= 2.5 u + 7 u
= 9.5 u
= 9.5 x 100
= 950
Answer(s): (a) 1000; (b) 950