PSLE
Bookstores T and U sell files of four colours. The bar graphs show the number of files sold by each shop in November. The bar for the number blue files sold by Bookstore T has not been drawn.

1. Half of the files sold by Bookstore T were blue files. How many blue files did Bookstore T sell?
2. Which colour(s) of files did Bookstore T sell less than Bookstore U? Give your answer(s) in letter(s) in alphabetical order. (Eg Blue, Red = B, R)
3. In December, Bookstore U sold 40 less pink files than the number of pink files sold in November. What was the percentage increase in the number of pink files sold by Bookstore U from November to December?

(a)
Number of purple files sold in Bookstore T = 100
Number of pink files sold in Bookstore T = 175
Number of yellow files sold in Bookstore T = 250

Since blue files sold in Bookstore T is half of the files sold by Bookstore T, the total of pink files, yellow files and purple files is equal to blue files.

Number of blue files sold in Bookstore T
= 175 + 250 + 100
= 525

(b)
Number of purple files sold in Bookstore T = 100 (Less) 
Number of purple files sold in Bookstore U = 225

Number of pink files sold in Bookstore T = 175 (More)
Number of pink files sold in Bookstore U = 125

Number of yellow files sold in Bookstore T = 250 (Equal)
Number of yellow files sold in Bookstore U = 250

Number of blue files sold in Bookstore T = 525 (More) 
Number of blue files sold in Bookstore U = 200 

Colour(s) of files that Bookstore T sold less than Bookstore U = Purple (P)

(c)
Percentage decrease in the number of pink files sold by Bookstore U from November to December
= ⁴⁰₁₂₅ x 100%
= ⁸₂₅ x 100%
= 32%

Answer(s): (a) 525; (b) P; (c) 32%