We have to find how many liters of saltwater Ruby scooped, but we have the value on milliliters; in fact, we know that she scooped 25,000.
So, for finding the value in liters, we will convert the value 25.000 milliliters to liters.
In this case, we remember that 1 liter is equivalent to 1000 milliliters, and then:
This means that 25000 milliliters of saltwater are 25 liters, and then Ruby scooped 25 liters of saltwater from her boat.