PSLE
Book Shops P and Q sell files of four colours. The bar graphs show the number of files sold by each shop in October. The bar for the number orange files sold by Book Shop P has not been drawn.

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

(a)
Number of green files sold in Book Shop P = 175
Number of blue files sold in Book Shop P = 100
Number of purple files sold in Book Shop P = 75

Since orange files sold in Book Shop P is half of the files sold by Book Shop P, the total of green files, blue files and purple files is equal to orange files.

Number of orange files sold in Book Shop P
= 175 + 100 + 75
= 350

(b)
Number of green files sold in Book Shop P = 175 (More)
Number of green files sold in Book Shop Q = 25

Number of blue files sold in Book Shop P = 100 (Equal)
Number of blue files sold in Book Shop Q = 100

Number of purple files sold in Book Shop P = 75 (Less) 
Number of purple files sold in Book Shop Q = 225

Number of orange files sold in Book Shop P = 350 (More) 
Number of orange files sold in Book Shop Q = 150 

Colour(s) of files that Book Shop P sold less than Book Shop Q = Purple (P)

(c)
Percentage increase in the number of green files sold by Book Shop Q from October to November
= ¹⁵₂₅ x 100%
= ³₅ x 100%
= 60%

Answer(s): (a) 350; (b) P; (c) 60%