#In this question I think we should not ignore two following possible cases:
1. Salesman's sales fewer than 1000.
2. Or above 1000.
1. Formula would be 300 = 10% of sales, i.e sales=3000, which is not possible against 300 dollars for this DS. question.
2. above 1000, i.e 300 + 0.05 (S-1000) = 0.01S which is sufficient to give answer.
My emphasis is on a scenario: modified statement 1 : Sales man income was 50% of his total sale.
In that case both cases will produce different permissible values for S, which we should keep in mind.
2. S=555.55 approx and that will make statement 1 insufficient.
For stem question, answer D is right.
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