A:40%
If you put 60 over 150 and x(percent of students) over 100 and cross multiply 100 and 60, you will get 6000. You then divide that by 150 which leaves you with 40 as x and 40 over 100 is 40%.
Answer: 12 red balls must be added
Step-by-step explanation:
Starting out with 15 balls, 6 red implies 9 blue. If blue remains 9, then we expect red to be 18 for a probability at 2/3. 18-6 = 12
F(x)= 650(1+.12)^x
f(x) = 650(1.12)^x
<u>Answer</u>

<u>Detailed Explanation </u>
To simply answer this, since .189 has three digits we are going to be inserting 999 as the denominator since it is a repeating decimal.

We could simplify the answer!

Therefore, the answer would simply be 

<u>Always Remember </u>
In the future, always remember whenever you have a three digit decimal and the problem asks you to convert it into a fraction, you should always insert 1000 as the denominator (the numerator is basically the decimal without the decimal point) and simplify if necessary.