{V1} mL of 0.100 M HCl is placed in a {V2}.0 mL volumetric flask and water is added to bring the final volume up to 250.0 mL. What is the molarity of the dilute solution?

Answer 1

It was 0.1 in the V1 (whatever volume that is) and you diluted it to 250 sothe new concn is
It's 0.1 x (V1/250) = ?
I don't know why you wrote it was placed in a V2.0 volumetric flask. If it were brought to 250.0 mL I would assume it was placed in a 250 mL flask.