PSLE
Bookstores P and Q sell rulers of four colours. The bar graphs show the number of rulers sold by each shop in July. The bar for the number pink rulers sold by Bookstore P has not been drawn.

1. Half of the rulers sold by Bookstore P were pink rulers. How many pink rulers did Bookstore P sell?
2. Which colour(s) of rulers did Bookstore P sell less than Bookstore Q? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In August, Bookstore Q sold 40 less green rulers than the number of green rulers sold in July. What was the percentage increase in the number of green rulers sold by Bookstore Q from July to August?

(a)
Number of yellow rulers sold in Bookstore P = 125
Number of green rulers sold in Bookstore P = 225
Number of orange rulers sold in Bookstore P = 125

Since pink rulers sold in Bookstore P is half of the rulers sold by Bookstore P, the total of green rulers, orange rulers and yellow rulers is equal to pink rulers.

Number of pink rulers sold in Bookstore P
= 225 + 125 + 125
= 475

(b)
Number of yellow rulers sold in Bookstore P = 125 (Less) 
Number of yellow rulers sold in Bookstore Q = 200

Number of green rulers sold in Bookstore P = 225 (More)
Number of green rulers sold in Bookstore Q = 100

Number of orange rulers sold in Bookstore P = 125 (Equal)
Number of orange rulers sold in Bookstore Q = 125

Number of pink rulers sold in Bookstore P = 475 (More) 
Number of pink rulers sold in Bookstore Q = 175 

Colour(s) of rulers that Bookstore P sold less than Bookstore Q = Yellow (Y)

(c)
Percentage decrease in the number of green rulers sold by Bookstore Q from July to August
= ⁴⁰₁₀₀ x 100%
= ²₅ x 100%
= 40%

Answer(s): (a) 475; (b) Y; (c) 40%