PSLE
Book Shops Q and R sell staplers of four colours. The bar graphs show the number of staplers sold by each shop in August. The bar for the number pink staplers sold by Book Shop Q has not been drawn.

1. Half of the staplers sold by Book Shop Q were pink staplers. How many pink staplers did Book Shop Q sell?
2. Which colour(s) of staplers did Book Shop Q sell less than Book Shop R? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In September, Book Shop R sold 30 more orange staplers than the number of orange staplers sold in August. What was the percentage increase in the number of orange staplers sold by Book Shop R from August to September?

(a)
Number of orange staplers sold in Book Shop Q = 175
Number of yellow staplers sold in Book Shop Q = 125
Number of green staplers sold in Book Shop Q = 100

Since pink staplers sold in Book Shop Q is half of the staplers sold by Book Shop Q, the total of orange staplers, yellow staplers and green staplers is equal to pink staplers.

Number of pink staplers sold in Book Shop Q
= 175 + 125 + 100
= 400

(b)
Number of orange staplers sold in Book Shop Q = 175 (More)
Number of orange staplers sold in Book Shop R = 125

Number of yellow staplers sold in Book Shop Q = 125 (Equal)
Number of yellow staplers sold in Book Shop R = 125

Number of green staplers sold in Book Shop Q = 100 (Less) 
Number of green staplers sold in Book Shop R = 250

Number of pink staplers sold in Book Shop Q = 400 (More) 
Number of pink staplers sold in Book Shop R = 75 

Colour(s) of staplers that Book Shop Q sold less than Book Shop R = Green (G)

(c)
Percentage increase in the number of orange staplers sold by Book Shop R from August to September
= ³⁰₁₂₅ x 100%
= ⁶₂₅ x 100%
= 24%

Answer(s): (a) 400; (b) G; (c) 24%