Math Is Fun Forum

Hi,
how to solve this puzzle:

A customer at a 7-11 store selected four items to buy, and was told that the cost was $7.11. He was curious that the cost was the same as the store name, so he enquired as to how the figure was derived. The clerk said that he had simply multiplied the prices of the four individual items. The customer protested that the four prices should have been ADDED, not MULTIPLIED. The clerk said that that was OK with him, but, the result was still the same: exactly $7.11. What were the four prices?

One way to solve this problem that comes immediately to mind is to factorize 711000 using some integer factorization rules. Is this the correct method or is there any smarter way to solve this quickly and without less work? Also here we know that we can convert the dollar amount to cents and which must be integer. But in general the quantity under consideration(7.11) might be any fraction (like electric current or amount of water) in this case is it possible to do factorization of fractions?

Thanks.