Dear Aspirant,

NEET marks conversion to percentile-

Evaluation of percentile on the basis of marks can easily be done. Here is an example by which you can easily understand the method- For it, I am giving an example

If A has scored 295 in NEET and 396 is the highest score obtained by topper of NEET, then the percentile of A will be calculated as are follows:

295 x 100/396 = 74.49

Answering your 2nd part-

First we need to understand what a dilution is:
A dilution is when you have a solution of a certain concentration and you add more solvent (remember: the substance that does the dissolving!) to decrease the concentration. If you are adding more solvent, the volume of the whole solution is going to increase as the concentration of the solution decreases. You can solve for the concentration or volume of the concentrated or dilute solution using the equation: M1V1 = M2V2, where M1 is the concentration in molarity (moles/Liters) of the concentrated solution, V2 is the volume of the concentrated solution, M2 is the concentration in molarity of the dilute solution (after more solvent has been added), and V2 is the volume of the dilute solution.

I hope this information helped you.

Thank you.