Even using both statements, we do not have even close to enough information to answer. Even just taking the simplest possible situation, where the supplier sold one heater of each type -- the tankless heater for $80,000 and the tank heater for $20,000 -- all we know is that the supplier makes a profit of $400 on the tankless heater. We have no information at all about the profit from the sale of the tank heater (it could be anything from $0 to $20,000, assuming it didn't take a loss). So even in that one specific situation, we can't answer the question, and the answer is E.
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A supplier sold two types of water heaters in 2017, tankless water heaters and tank water heaters. In 2017, what was the supplier’s total water heater profit as a percent of total water heater revenue?

Profit/Revenue=?


(1) The supplier’s profit on tankless water heaters was $400 per unit sold.
>> what about tank water heater: incomplete information

(2) The supplier’s selling price for each tank water heater was 25% of the supplier’s selling price for each tankless water heater, and the supplier’s total water heater revenue was $100,000.
TW = 25% of TLW(price)
Profit is not given.
Quantity is not given

1+2:

TLW( profit) = 400$ | Price: (x-400)
TW(profit)= ? | Price : (x-400)/25%= 5/4(x-400)
Total Revenue = 100k
Quantity is not given
Not sufficient

Hence E answer

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