80.0 mL of distilled water is added to a 40.0 mL 0.170 M solution of ethanol. What is the molarity of ethanol in the resulting solution?

0.170 x (40/120) = ? OR use the dilution formula of

mL1 x M1 = mL2 x M2.
40 x 0.170 = 120 x M2