A book store had 195 comics. There were Malay, Chinese and English comics in the ratio of 2 : 7 : 4. When the book store assistant brought in another 138 new comics, the number of Malay comics was increased by 60% and the number of Chinese comics was increased by ⁶₇.

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

	Malay	Chinese	English	Total
Before	2 u	7 u	4 u	195
Change	+ 1.2 u	+ 6 u	+ ?	+ 138
After	3.2 u	13 u	6 u	333

Increase in the number of Malay comics
= 60% x 2 u
= ⁶⁰₁₀₀ x 2 u
= 1.2 u

Increase in the number of Chinese comics
= ⁶₇ x 7 u
= 6 u

Total number of comics at first
= 2 u + 7 u + 4 u
= 13 u

13 u = 195

1 u = 195 ÷ 13 = 15

Increase in the number of Malay and Chinese comics
= 1.2 u + 6 u
= 7.2 u
= 7.2 x 15
= 108

Number of English comics brought in
= 138 - 108
= 30 

(b)
Number of English comics at first
= 4 u
= 4 x 15
= 60

Percentage increase in English comics
= ³⁰₆₀ x 100%
= 50%

Answer(s): (a) 30; (b) 50%