PSLE Warren had silver files and red files for sale. He sold 240 silver files. 60% of the files sold were red.
- How many silver files and red files did Warren sell altogether?
- He sold 50% of his files. 75% of the files left unsold were silver. How many red files did Warren have at first?
| |
Silver |
Red |
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 red files sold = 3 u
Number of silver files sold
= 5 u - 3 u
= 2 u
2 u = 240
1 u = 240 ÷ 2 = 120
Total number of files sold
= 5 u
= 5 x 120
= 600
(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 silver = 75%
Percent of the files left unsold that were red = 100% - 75% = 25%
Number of the files left unsold that were red
= 25% x 5 u
=
25100 x 5 u
= 1.25 u
Number of red files that Warren had at first
= 1.25 u + 3 u
= 4.25 u
= 4.25 x 120
= 510
Answer(s): (a) 600; (b) 510
