Answer: 9
Step-by-step explanation: There are multiple ways to solve this.
One way is to simply multiply 0.6 by 15, getting you 9.
Another way is to use proportions. 0.6 is the same as 3/5, and we need to find n in 3/5 = n/15. We can do this by cross-multiplying, getting us 45/5=9