10 ml of a 0.25M solution is diluted to make exactly 250 ml of solution. What's the concentration of the diluted solution?

0.01 M

Explanation:

As this problem deals with a dilution process, we can solve it by using the following formula:

Where subscript 1 stands for the initial concentration and volume, while 2 stands for the final conditions.

That means that in this case:

We input the given data:

3 hours because it is a decent distance.