How to convert foot, yards, miles to km

Although I lived in the Channel Islands for 8 years, I still can't work out yards, foot, miles!!

1 inch (pouce) = 2,54 centimètres

1 foot (pied) = 30,48 centimètres

1 yard (verge) = 0,9144 mètre

1 mile = 1,6093 km

1 km = 0,6214 mile

1 nautical mile (mille marin) = 1,852 km