PSLE
Shops Y and Z sell files of four colours. The bar graphs show the number of files sold by each shop in September. The bar for the number green files sold by Shop Y has not been drawn.

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

(a)
Number of purple files sold in Shop Y = 175
Number of blue files sold in Shop Y = 175
Number of orange files sold in Shop Y = 100

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

Number of green files sold in Shop Y
= 175 + 175 + 100
= 450

(b)
Number of purple files sold in Shop Y = 175 (More)
Number of purple files sold in Shop Z = 75

Number of blue files sold in Shop Y = 175 (Equal)
Number of blue files sold in Shop Z = 175

Number of orange files sold in Shop Y = 100 (Less) 
Number of orange files sold in Shop Z = 200

Number of green files sold in Shop Y = 450 (More) 
Number of green files sold in Shop Z = 200 

Colour(s) of files that Shop Y sold less than Shop Z = Orange (O)

(c)
Percentage increase in the number of purple files sold by Shop Z from September to October
= ³⁰₇₅ x 100%
= ²₅ x 100%
= 40%

Answer(s): (a) 450; (b) O; (c) 40%