A box containing 60 chocolates amongst Ann, Marie and James in the ratio 3:4:5. How many chocolate?

If Ann gets 3 pieces of chocolate, then Marie will get 4 and James 5, right?
Well, 3 + 4 + 5 = 12 and 60, the total of Chocolate pieces, is divisible by 12 without remainder:
60 / 12 = 5.
Now,
5 (3 + 4 + 5) = 60, then
Ann gets 5 * 3 = 15,
Marie gets 5 * 4 = 20 and
James gets 5 * 5 = 25 pieces of chocolate.
I hope they've got a good dentist, too ;-)