PSLE Ian had orange files and silver files for sale. He sold 40 orange files. 60% of the files sold were silver.
- How many orange files and silver files did Ian sell altogether?
- He sold 50% of his files. 75% of the files left unsold were orange. How many silver files did Ian have at first?
| |
Orange |
Silver |
Total |
Total in percent |
| Before |
5.75 u |
4.25 u |
10 u |
100% |
| Change |
- 40%
- 2 u |
- 60%
- 3 u |
- 100%
- 5 u |
- 50% |
| After |
75%
3.75 u |
25%
1.25 u |
100%
5 u |
50%
|
60% =
60100 =
35 Total number of files sold = 5 u
Number of silver files sold = 3 u
Number of orange files sold
= 5 u - 3 u
= 2 u
2 u = 40
1 u = 40 ÷ 2 = 20
Total number of files sold
= 5 u
= 5 x 20
= 100
(b)
Percent of the files left unsold = 100% - 50% = 50% 50% of the files that were sold = 5 u 50% of the files that were left unsold = 5 u Percent of the files left unsold that were orange = 75%
Percent of the files left unsold that were silver = 100% - 75% = 25%
Number of the files left unsold that were silver
= 25% x 5 u
=
25100 x 5 u
= 1.25 u
Number of silver files that Ian had at first
= 1.25 u + 3 u
= 4.25 u
= 4.25 x 20
= 85
Answer(s): (a) 100; (b) 85
