Test ur logic, Probability question

[pif]

*Given that in some population a 1% of them r infected by some disease.
*And given that there is a medical test that can recognize the disease, the test results r positive or negative, But the test results r true only in 90% from the tests.

*The Problem: a man from this population made the test, and the result was Positive(sick), what the odds that this man is Realy sick? [img]/images/graemlins/confused.gif[/img]