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

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

(a)
Number of green files sold in Book Shop D = 50
Number of yellow files sold in Book Shop D = 250
Number of blue files sold in Book Shop D = 175

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

Number of orange files sold in Book Shop D
= 250 + 175 + 50
= 475

(b)
Number of green files sold in Book Shop D = 50 (Less) 
Number of green files sold in Book Shop E = 150

Number of yellow files sold in Book Shop D = 250 (More)
Number of yellow files sold in Book Shop E = 75

Number of blue files sold in Book Shop D = 175 (Equal)
Number of blue files sold in Book Shop E = 175

Number of orange files sold in Book Shop D = 475 (More) 
Number of orange files sold in Book Shop E = 150 

Colour(s) of files that Book Shop D sold less than Book Shop E = Green (G)

(c)
Percentage decrease in the number of yellow files sold by Book Shop E from April to May
= ¹⁵₇₅ x 100%
= ¹₅ x 100%
= 20%

Answer(s): (a) 475; (b) G; (c) 20%