GMAT Critical Reasoning (CR) | Re: Evaluate 2: Income Tax fraud

To determine the extent of tax fraud, the Internal Revenue Service audited the current year tax returns of a random set of 1000 individuals. Even though only 10% of the individuals in the group were self-employed (other 90% were working professionals), they accounted for 50% of the fraudulent cases.

Pre-thinking

se = 100
Professional =900

assume that total fraudulent case = 100
then 50 fraudulent cases belong to s.e. & honest cases = 50

Now we can't draw ratio proposition of total money
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