It is given that the total expense for the company = 100,000 + 5% of total revenue (let say, x)
Also, the project made profit.
Profit = Total revenue - expenses = x - (100000 + 0.05x) = 0.95x - 100000
Since profit > 0
therefore, 0.95x - 100000 > 0 ...(a)
using (1) The company's total revenue from the sale of product X last year was greater than $110,000,
we can only check whether 0.95x - 100000 is positive or not. Insufficient.
using (2) For each unit of product X sold last year, the company's revenue was $5,
lets find the minimum number of units,
number of units = total revenue/5 = x/5
or 0.95(x/5) - 100000 >0 ....(from (a))
or x > 21052, thus x is greater than 21000. Sufficient.
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