PSLE
Book Shops G and H sell notebooks of four colours. The bar graphs show the number of notebooks sold by each shop in July. The bar for the number green notebooks sold by Book Shop G has not been drawn.

1. Half of the notebooks sold by Book Shop G were green notebooks. How many green notebooks did Book Shop G sell?
2. Which colour(s) of notebooks did Book Shop G sell less than Book Shop H? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In August, Book Shop H sold 50 less orange notebooks than the number of orange notebooks sold in July. What was the percentage increase in the number of orange notebooks sold by Book Shop H from July to August?

(a)
Number of purple notebooks sold in Book Shop G = 125
Number of orange notebooks sold in Book Shop G = 225
Number of yellow notebooks sold in Book Shop G = 100

Since green notebooks sold in Book Shop G is half of the notebooks sold by Book Shop G, the total of orange notebooks, yellow notebooks and purple notebooks is equal to green notebooks.

Number of green notebooks sold in Book Shop G
= 225 + 100 + 125
= 450

(b)
Number of purple notebooks sold in Book Shop G = 125 (Less) 
Number of purple notebooks sold in Book Shop H = 200

Number of orange notebooks sold in Book Shop G = 225 (More)
Number of orange notebooks sold in Book Shop H = 100

Number of yellow notebooks sold in Book Shop G = 100 (Equal)
Number of yellow notebooks sold in Book Shop H = 100

Number of green notebooks sold in Book Shop G = 450 (More) 
Number of green notebooks sold in Book Shop H = 175 

Colour(s) of notebooks that Book Shop G sold less than Book Shop H = Purple (P)

(c)
Percentage decrease in the number of orange notebooks sold by Book Shop H from July to August
= ⁵⁰₁₀₀ x 100%
= ¹₂ x 100%
= 50%

Answer(s): (a) 450; (b) P; (c) 50%