PSLE
Shops N and P sell notebooks of four colours. The bar graphs show the number of notebooks sold by each shop in October. The bar for the number pink notebooks sold by Shop N has not been drawn.

1. Half of the notebooks sold by Shop N were pink notebooks. How many pink notebooks did Shop N sell?
2. Which colour(s) of notebooks did Shop N sell less than Shop P? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In November, Shop P sold 15 less purple notebooks than the number of purple notebooks sold in October. What was the percentage increase in the number of purple notebooks sold by Shop P from October to November?

(a)
Number of orange notebooks sold in Shop N = 30
Number of purple notebooks sold in Shop N = 90
Number of green notebooks sold in Shop N = 100

Since pink notebooks sold in Shop N is half of the notebooks sold by Shop N, the total of purple notebooks, green notebooks and orange notebooks is equal to pink notebooks.

Number of pink notebooks sold in Shop N
= 90 + 100 + 30
= 220

(b)
Number of orange notebooks sold in Shop N = 30 (Less) 
Number of orange notebooks sold in Shop P = 60

Number of purple notebooks sold in Shop N = 90 (More)
Number of purple notebooks sold in Shop P = 20

Number of green notebooks sold in Shop N = 100 (Equal)
Number of green notebooks sold in Shop P = 100

Number of pink notebooks sold in Shop N = 220 (More) 
Number of pink notebooks sold in Shop P = 40 

Colour(s) of notebooks that Shop N sold less than Shop P = Orange (O)

(c)
Percentage decrease in the number of purple notebooks sold by Shop P from October to November
= ¹⁵₂₀ x 100%
= ³₄ x 100%
= 75%

Answer(s): (a) 220; (b) O; (c) 75%