PSLE
Stationery Kiosks L and M sell post-it-pads of four colours. The bar graphs show the number of post-it-pads sold by each shop in October. The bar for the number purple post-it-pads sold by Stationery Kiosk L has not been drawn.

1. Half of the post-it-pads sold by Stationery Kiosk L were purple post-it-pads. How many purple post-it-pads did Stationery Kiosk L sell?
2. Which colour(s) of post-it-pads did Stationery Kiosk L sell less than Stationery Kiosk M? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In November, Stationery Kiosk M sold 5 more yellow post-it-pads than the number of yellow post-it-pads sold in October. What was the percentage increase in the number of yellow post-it-pads sold by Stationery Kiosk M from October to November?

(a)
Number of yellow post-it-pads sold in Stationery Kiosk L = 30
Number of orange post-it-pads sold in Stationery Kiosk L = 20
Number of blue post-it-pads sold in Stationery Kiosk L = 5

Since purple post-it-pads sold in Stationery Kiosk L is half of the post-it-pads sold by Stationery Kiosk L, the total of yellow post-it-pads, orange post-it-pads and blue post-it-pads is equal to purple post-it-pads.

Number of purple post-it-pads sold in Stationery Kiosk L
= 30 + 20 + 5
= 55

(b)
Number of yellow post-it-pads sold in Stationery Kiosk L = 30 (More)
Number of yellow post-it-pads sold in Stationery Kiosk M = 25

Number of orange post-it-pads sold in Stationery Kiosk L = 20 (Equal)
Number of orange post-it-pads sold in Stationery Kiosk M = 20

Number of blue post-it-pads sold in Stationery Kiosk L = 5 (Less) 
Number of blue post-it-pads sold in Stationery Kiosk M = 45

Number of purple post-it-pads sold in Stationery Kiosk L = 55 (More) 
Number of purple post-it-pads sold in Stationery Kiosk M = 35 

Colour(s) of post-it-pads that Stationery Kiosk L sold less than Stationery Kiosk M = Blue (B)

(c)
Percentage increase in the number of yellow post-it-pads sold by Stationery Kiosk M from October to November
= ⁵₂₅ x 100%
= ¹₅ x 100%
= 20%

Answer(s): (a) 55; (b) B; (c) 20%