A book store had 315 comics. There were Chinese, English and Malay comics in the ratio of 1 : 2 : 4. When the book store assistant brought in another 162 new comics, the number of Chinese comics was increased by 60% and the number of English comics was increased by
12.
- What was the number of Malay comics that the book store assistant brought in?
- What was the percentage increase in the number of Malay comics?
|
Chinese |
English |
Malay |
Total |
Before |
1 u |
2 u |
4 u |
315 |
Change |
+ 0.6 u |
+ 1 u |
+ ? |
+ 162 |
After |
1.6 u |
3 u |
6 u |
477 |
Increase in the number of Chinese comics
= 60% x 1 u
=
60100 x 1 u
= 0.6 u
Increase in the number of English comics
=
12 x 2 u
= 1 u
Total number of comics at first
= 1 u + 2 u + 4 u
= 7 u
7 u = 315
1 u = 315 ÷ 7 = 45
Increase in the number of Chinese and English comics
= 0.6 u + 1 u
= 1.6 u
= 1.6 x 45
= 72
Number of Malay comics brought in
= 162 - 72
= 90
(b)
Number of Malay comics at first
= 4 u
= 4 x 45
= 180
Percentage increase in Malay comics
=
90180 x 100%
= 50%
Answer(s): (a) 90; (b) 50%