Answer: 2.83 minutes
Explanation:
It is understood that trains are approaching. That is, they have speeds of equal magnitude but opposite. When train A travels x meters northbound, then train B travels the same distance southbound.
Therefore trains approach at a speed of:

Then:

Where x is the distance between the trains

So the time in which both trains meet is:

This is:

<em />
<em>How long will it be before they reach one another ?</em>
<h3>2.83 minutes</h3>
It's solubility. Solubility is a measure of the ability of a solute to dissolve in a solvent; maximum amount of solute that will dissolve in solvent at a specific temperature. Solute is substance being dissolved. Solvent is the substance that is doing the dissolving; the part of the solution that is present in the greatest quantity.