We have a solution of c5h10o2 of concentration 4 m. find out the volume we need to take from this solution to make a 250 ml solution of concentration 0.5 m.

is my result right? i got 31.25 ml

here's what i did:
m=moles solute / volume (l) solution (m=n/v)
first i calculate the moles of acid needed for a 0.5m, 0.25l solution.
n=m*v = 0.5*0.25 = 0.125 mol acid
now knowing how many moles i need to take, i calculate the volume those moles occupy in the 4m solution.
v=n/m = 0.125/4 = 0.03125 l solution = 31.25 ml
so you need to take 31.25 ml of 4m acid solution and add 218.75 (250*31.25) of water to make a 0.5m, 250 ml solution.