A book store had 480 magazines. There were Chinese, English and Malay magazines in the ratio of 3 : 8 : 5. When the book store assistant brought in another 156 new magazines, the number of Chinese magazines was increased by 40% and the number of English magazines was increased by ¹₄.

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

	Chinese	English	Malay	Total
Before	3 u	8 u	5 u	480
Change	+ 1.2 u	+ 2 u	+ ?	+ 156
After	4.2 u	10 u	7 u	636

Increase in the number of Chinese magazines
= 40% x 3 u
= ⁴⁰₁₀₀ x 3 u
= 1.2 u

Increase in the number of English magazines
= ¹₄ x 8 u
= 2 u

Total number of magazines at first
= 3 u + 8 u + 5 u
= 16 u

16 u = 480

1 u = 480 ÷ 16 = 30

Increase in the number of Chinese and English magazines
= 1.2 u + 2 u
= 3.2 u
= 3.2 x 30
= 96

Number of Malay magazines brought in
= 156 - 96
= 60 

(b)
Number of Malay magazines at first
= 5 u
= 5 x 30
= 150

Percentage increase in Malay magazines
= ⁶⁰₁₅₀ x 100%
= 40%

Answer(s): (a) 60; (b) 40%