Answers

2014-01-09T19:36:17+08:00
The answer is 18. 

Solution:
30*3=90
90/5=18

Another solution:
30/5=6
6*3=18

The sum of the numbers should be divisible by 8 since 5+3=8. It means that the sum of the two numbers can be divided into 8 parts. The first ratio is 3/8 while the second is 5/8.

Checking:
18+30=48
48/8=6

3*6:5*6
18:30
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