After replacing his old gas water heater with a new, pilotless, gas water heater that is rated as highly efficient, Jimmy’s gas bills increased.
Each of the following, if true, contributes to an explanation of the increase mentioned above except:
(A) The new water heater uses a smaller percentage of the gas used by Jimmy’s household than did the old one.
(B) Shortly after the new water heater was installed, Jimmy’s uncle came to live with him, doubling the size of the household.
(C) After having done his laundry at a laundromat, Jimmy bought and started using a gas dryer when he replaced his water heater.
(D) Jimmy’s utility company raised the rates for gas consumption following installation of the new water heater.
(E) Unusually cold weather following installation of the new water heater resulted in heavy gas usage.
A. Incorrect. While it initially seems to explain the paradox by implying that other gas usage increased, it doesn’t fully resolve the issue. For example, if total gas usage actually decreased, the gas bill going up remains unexplained. A valid paradox resolution must work across all numerical possibilities.
B. Incorrect. Jimmy’s uncle taking longer showers would increase hot water use, possibly increasing gas consumption. But since the new heater is more efficient, this alone doesn’t fully explain a higher gas bill without knowing if that increase offsets the efficiency gains.
C. Correct. This directly resolves the paradox. Even though the water heater uses less gas, another new appliance could be increasing total gas use—explaining why the overall gas bill is higher.
D. Incorrect. The stimulus says Jimmy paid more, not necessarily that he used more gas. Higher costs could result from rate changes rather than consumption, which is what this option explains.
E. Incorrect. Cold weather could explain an increase in heating needs, which may boost gas usage despite the new heater’s efficiency. However, this introduces a speculative external factor not mentioned in the stimulus. While plausible, it’s less directly tied to the specific scenario than C.
