PSLE Liam had red markers and yellow markers for sale. He sold 70 red markers. 30% of the markers sold were yellow.
- How many red markers and yellow markers did Liam sell altogether?
- He sold 50% of his markers. 60% of the markers left unsold were red. How many yellow markers did Liam have at first?
|
Red |
Yellow |
Total |
Total in percent |
Before |
13 u |
7 u |
20 u |
100% |
Change |
- 70% - 7 u |
- 30% - 3 u |
- 100% - 10 u |
- 50% |
After |
60% 6 u |
40% 4 u |
100% 10 u |
50%
|
30% =
30100 =
310 Total number of markers sold = 10 u
Number of yellow markers sold = 3 u
Number of red markers sold
= 10 u - 3 u
= 7 u
7 u = 70
1 u = 70 ÷ 7 = 10
Total number of markers sold
= 10 u
= 10 x 10
= 100
(b)
Percent of the markers left unsold = 100% - 50% = 50% 50% of the markers that were sold = 10 u 50% of the markers that were left unsold = 10 u Percent of the markers left unsold that were red = 60%
Percent of the markers left unsold that were yellow = 100% - 60% = 40%
Number of the markers left unsold that were yellow
= 40% x 10 u
=
40100 x 10 u
= 4 u
Number of yellow markers that Liam had at first
= 4 u + 3 u
= 7 u
= 7 x 10
= 70
Answer(s): (a) 100; (b) 70