your supervisor has just asked you to prepare 500ml of 3.00M HNO3 solution for tomorrow's undergraduate experiment. The Stock Solutions cabinet is under the Stockroom Explorer. You will find find a 2.50 liter bottle containing 15.4M HNO3. Please prepare a flask containing 500ml of a 3.00M solution.
The dilution formula is
mL1 x M1 = mL2 x M2
500 mL x 3.00 M = mL2 x 15.4
Solve for mL2, place that amount of the 15.4 M stuff in a 500 mL volumetric flask, add DI or distilled H2O to the mark on the flask, stopper, mix thoroughly, label. Done.