PSLE
Stationery 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 blue notebooks sold by Stationery Shop N has not been drawn.

1. Half of the notebooks sold by Stationery Shop N were blue notebooks. How many blue notebooks did Stationery Shop N sell?
2. Which colour(s) of notebooks did Stationery Shop N sell less than Stationery Shop P? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In November, Stationery Shop P sold 30 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 Stationery Shop P from October to November?

(a)
Number of pink notebooks sold in Stationery Shop N = 40
Number of purple notebooks sold in Stationery Shop N = 90
Number of orange notebooks sold in Stationery Shop N = 90

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

Number of blue notebooks sold in Stationery Shop N
= 90 + 90 + 40
= 220

(b)
Number of pink notebooks sold in Stationery Shop N = 40 (Less) 
Number of pink notebooks sold in Stationery Shop P = 100

Number of purple notebooks sold in Stationery Shop N = 90 (More)
Number of purple notebooks sold in Stationery Shop P = 40

Number of orange notebooks sold in Stationery Shop N = 90 (Equal)
Number of orange notebooks sold in Stationery Shop P = 90

Number of blue notebooks sold in Stationery Shop N = 220 (More) 
Number of blue notebooks sold in Stationery Shop P = 50 

Colour(s) of notebooks that Stationery Shop N sold less than Stationery Shop P = Pink (P)

(c)
Percentage decrease in the number of purple notebooks sold by Stationery Shop P from October to November
= ³⁰₄₀ x 100%
= ³₄ x 100%
= 75%

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