A book shop had 880 magazines. There were Malay, Chinese and English magazines in the ratio of 4 : 7 : 5. When the book shop assistant brought in another 583 new magazines, the number of Malay magazines was increased by 40% and the number of Chinese magazines was increased by ⁵₇.

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

	Malay	Chinese	English	Total
Before	4 u	7 u	5 u	880
Change	+ 1.6 u	+ 5 u	+ ?	+ 583
After	5.6 u	12 u	9 u	1463

Increase in the number of Malay magazines
= 40% x 4 u
= ⁴⁰₁₀₀ x 4 u
= 1.6 u

Increase in the number of Chinese magazines
= ⁵₇ x 7 u
= 5 u

Total number of magazines at first
= 4 u + 7 u + 5 u
= 16 u

16 u = 880

1 u = 880 ÷ 16 = 55

Increase in the number of Malay and Chinese magazines
= 1.6 u + 5 u
= 6.6 u
= 6.6 x 55
= 363

Number of English magazines brought in
= 583 - 363
= 220 

(b)
Number of English magazines at first
= 5 u
= 5 x 55
= 275

Percentage increase in English magazines
= ²²⁰₂₇₅ x 100%
= 80%

Answer(s): (a) 220; (b) 80%