A book store had 315 fiction books. There were Chinese, English and Malay fiction books in the ratio of 7 : 6 : 8. When the book store assistant brought in another 126 new fiction books, the number of Chinese fiction books was increased by 20% and the number of English fiction books was increased by ¹₂.

1. What was the number of Malay fiction books that the book store assistant brought in?
2. What was the percentage increase in the number of Malay fiction books?

	Chinese	English	Malay	Total
Before	7 u	6 u	8 u	315
Change	+ 1.4 u	+ 3 u	+ ?	+ 126
After	8.4 u	9 u	12 u	441

Increase in the number of Chinese fiction books
= 20% x 7 u
= ²⁰₁₀₀ x 7 u
= 1.4 u

Increase in the number of English fiction books
= ¹₂ x 6 u
= 3 u

Total number of fiction books at first
= 7 u + 6 u + 8 u
= 21 u

21 u = 315

1 u = 315 ÷ 21 = 15

Increase in the number of Chinese and English fiction books
= 1.4 u + 3 u
= 4.4 u
= 4.4 x 15
= 66

Number of Malay fiction books brought in
= 126 - 66
= 60 

(b)
Number of Malay fiction books at first
= 8 u
= 8 x 15
= 120

Percentage increase in Malay fiction books
= ⁶⁰₁₂₀ x 100%
= 50%

Answer(s): (a) 60; (b) 50%