PSLE Nick had gold files and yellow files for sale. He sold 60 gold files. 60% of the files sold were yellow.
- How many gold files and yellow files did Nick sell altogether?
- He sold 50% of his files. 70% of the files left unsold were gold. How many yellow files did Nick have at first?
| |
Gold |
Yellow |
Total |
Total in percent |
| Before |
5.5 u |
4.5 u |
10 u |
100% |
| Change |
- 40%
- 2 u |
- 60%
- 3 u |
- 100%
- 5 u |
- 50% |
| After |
70%
3.5 u |
30%
1.5 u |
100%
5 u |
50%
|
60% =
60100 =
35 Total number of files sold = 5 u
Number of yellow files sold = 3 u
Number of gold files sold
= 5 u - 3 u
= 2 u
2 u = 60
1 u = 60 ÷ 2 = 30
Total number of files sold
= 5 u
= 5 x 30
= 150
(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 gold = 70%
Percent of the files left unsold that were yellow = 100% - 70% = 30%
Number of the files left unsold that were yellow
= 30% x 5 u
=
30100 x 5 u
= 1.5 u
Number of yellow files that Nick had at first
= 1.5 u + 3 u
= 4.5 u
= 4.5 x 30
= 135
Answer(s): (a) 150; (b) 135
