PSLE
Jeremy had purple markers and yellow markers for sale. He sold 100 purple markers. 60% of the markers sold were yellow.

1. How many purple markers and yellow markers did Jeremy sell altogether?
2. He sold 50% of his markers. 75% of the markers left unsold were purple. How many yellow markers did Jeremy have at first?

	Purple	Yellow	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 markers sold = 5 u
Number of yellow markers sold = 3 u

Number of purple markers sold
= 5 u - 3 u
= 2 u

2 u = 100

1 u = 100 ÷ 2 = 50

Total number of markers sold
= 5 u
= 5 x 50
= 250

(b)
Percent of the markers left unsold
= 100% - 50%
= 50%

50% of the markers that were sold = 5 u
50% of the markers that were left unsold = 5 u

Percent of the markers left unsold that were purple = 75%
Percent of the markers left unsold that were yellow = 100% - 75% = 25%

Number of the markers left unsold that were yellow
= 25% x 5 u
= ²⁵₁₀₀ x 5 u
= 1.25 u

Number of yellow markers that Jeremy had at first
= 1.25 u + 3 u
= 4.25 u
= 4.25 x 50
= 212.5

Answer(s): (a) 250; (b) 212.5