A book store had 510 magazines. There were Chinese, English and Malay magazines in the ratio of 7 : 2 : 8. When the book store assistant brought in another 252 new magazines, the number of Chinese magazines was increased by 20% and the number of English magazines was increased by
12.
- What was the number of Malay magazines that the book store assistant brought in?
- What was the percentage increase in the number of Malay magazines?
|
Chinese |
English |
Malay |
Total |
Before |
7 u |
2 u |
8 u |
510 |
Change |
+ 1.4 u |
+ 1 u |
+ ? |
+ 252 |
After |
8.4 u |
3 u |
14 u |
762 |
Increase in the number of Chinese magazines
= 20% x 7 u
=
20100 x 7 u
= 1.4 u
Increase in the number of English magazines
=
12 x 2 u
= 1 u
Total number of magazines at first
= 7 u + 2 u + 8 u
= 17 u
17 u = 510
1 u = 510 ÷ 17 = 30
Increase in the number of Chinese and English magazines
= 1.4 u + 1 u
= 2.4 u
= 2.4 x 30
= 72
Number of Malay magazines brought in
= 252 - 72
= 180
(b)
Number of Malay magazines at first
= 8 u
= 8 x 30
= 240
Percentage increase in Malay magazines
=
180240 x 100%
= 75%
Answer(s): (a) 180; (b) 75%