Most household appliances use electricity only when in use. Many micro

Question

Most household appliances use electricity only when in use. Many microwave ovens, however, have built-in clocks and so use some electricity even when they are not in use. The clocks each consume about 45 kilowatt-hours per year. Therefore, households whose microwave oven has no built-in clock use 45 kilowatt-hours per year less, on average, than do comparable households whose microwave oven is otherwise similar but has a built-in clock.

Which of the following is an assumption on which the argument depends?

(A) Households that do not have a microwave oven use less energy per year, on average, than do households that have a microwave oven.

(B) Microwave ovens with a built-in clock do not generally cost more to buy than microwave ovens without a built-in clock.

(C) All households that have a microwave oven also have either a gas oven or a conventional electric oven.

(D) Households whose microwave oven does not have a built-in clock are no more likely to have a separate electric clock plugged in than households whose microwave oven has one.

(E) There are more households that have a microwave oven with a built-in clock than there are households that have a microwave oven without a built-in clock.

(A) - reiterates the stimulus 
(B) - information is irrelevant to the discussion
(C) - additional information to the stimulus - not helpful in addressing the issue at hand
(D) - stating that if an oven don't have a clock will not install one so - these ovens most likely to be less expensive than the oven's with the build in clocks. - tempting answer
(E) - Additional information to the stimulus - Not quite relevant. 
I don't have the OA but I'm going with D. Wait for your responses. Gracias.

seed · Accepted Answer

Which of the following is an assumption on which the argument depends?

Conclusion: Highlighted above.

(A)  Households that do not have a microwave oven  use less energy per year, on average, than do households that have a microwave oven.  - Incorrect. Conclusion is about household who have microwaves with clock and without clock. This talks about households that do not have microwave at all.

(B) Microwave ovens with a built-in clock do not generally  cost more  to buy than microwave ovens without a built-in clock.  - Incorrect. Again diverting from the conclusion. We have to focus on energy consumption.

(C) All households that have a microwave oven also have either a gas oven or a  conventional electric oven .  - Incorrect. Clearly, irrelevant.

(D) Households whose microwave oven does not have a built-in clock are no more likely to have a separate electric clock plugged in than households whose microwave oven has one.  - Correct. If households whose microwave oven does not have a built-in clock also don't have a separate clock (which will be equivalent to MW with clock) as a timer then yes, the conclusion is valid. These households will consume less energy.

Negation: If these households whose microwaves don't have clock have separate clock used as timer then the energy consumption of these households will be either same or more than households with microwave timer.

(E) There are  more  households that have a microwave oven with a built-in clock than there are households that have a microwave oven without a built-in clock.  - Incorrect. Conclusion is about energy and not about how many more house holds have microwave with clock.

Answer: (D).

bkk145 · Answer

D no doubt.

GMATBLACKBELT · Answer

I go for D.

A: irrelevant
B: irrelevant we aren't concerned about actual costs of the microwave.
C: irrelevant we aren't concerned about gas stoves or other appliances.
We wanna know why the microwave will use less power.
E: maybe, but this doesn't help the conclusion explain that these non-built in clock microwaves will use less power.

aragonn · Answer

A. Households that do not have a microwave oven use less energy per year, on average, than do households that have a microwave oven. --- it can't be true ! as it is comparing oven with non-oven.
B. Microwave ovens with a built-in clock do not generally cost more to buy than microwav e ovens without a built-in clock .--- nothing could support this. 
C. All households that have a microwave oven also have either a gas oven or a Conventional electric oven .---out of scope. 
D. Households whose microwave oven does not have a built-in clock are no more likely to have a separate electric clock plugged in than households whose microwave oven has one .--- i m giving this a chance cause others can't be an ans 
E. There are more households that have a microwave oven with a built-in clock than there are households that have a microwave oven without a built-in clock. --- out of scope

D it is .

Rashed12 · Answer

D is correct answer.

Households  whose microwave oven does not have a built-in clock  are no more likely to have a  separate electric clock  plugged in than  households whose microwave oven has one.

D states that This microwave has no electric clock. This electric clock needs electricity to run. Therefore, as this microwave has no electric clock, it will consume less electricity than those with microwave.

Assumption : Households whose microwave oven does not have a built-in clock are no more likely to have a separate electric clock plugged in than households whose microwave oven has one.

Conclusion : Therefore, households whose microwave oven has no built-in clock use 45 kilowatt-hours per year less, on average, than do comparable households microwave oven is otherwise similar but has a built-in clock.

gamebredfighter · Answer

MartyTargetTestPrep 
Its often difficult to decipher perplexed language like the one used in answer choice D
"Households whose microwave oven does not have a built-in clock are no more likely to have a separate electric clock plugged in than households whose microwave oven has one."
For example this means that they have the same probability both households to have a separate electric clock ?

The "no more likely" makes it difficult especially under time pressure to decode and grasp the exact meaning. Do u have any particular tips as how someone should approach such language and make it simpler so he gets its precise meaning?

minalgambhir · Answer

Let's go step by step

CONCLUSION - Households whose microwave ovens have no inbuilt clocks consume 45 KW/year less energy than households with microwaves with inbuilt clocks.

PRETHINKING-

IN WHAT SCENARIO the households with microwave ovens without inbuilt clocks do not consume 45KW/year less electricity

GIVEN THAT -

1) Many microwave ovens have inbuilt clocks and so consume electricity when not in use
2) Such microwaves use 45KW/year electricity

FALSIFICATION QUESTION - There may be some other source of clock used by the households to note the timing

ASSUMPTION - There is no other source of clock used by the households with microwaves without inbuilt clock

ANSWER CHOICE ANALYSIS-

A) Households with and without microwave ovens are not compared in the argument, whereas the households with microwave ovens with inbuilt clock and without inbuilt clock are compared

B) Cost factor not considered in the argument

C) Gas oven and electric ovens not talked about in the passage

D) CORRECT - Inline with our assumption

E) Number of households not concerned in the passage

CrackverbalGMAT · Answer

Most household appliances use electricity only when in use. Many microwave ovens, however, have built-in clocks and so use some electricity even when they are not in use. The clocks each consume about 45 kilowatt-hours per year. Therefore, households whose microwave oven has no built-in clock use 45 kilowatt-hours per year less, on average, than do comparable households whose microwave oven is otherwise similar but has a built-in clock.
Which of the following is an assumption on which the argument depends?

A. Households that do not have a microwave oven use less energy per year, on average, than do households that have a microwave oven.
B. Microwave ovens with a built-in clock do not generally cost more to buy than microwave ovens without a built-in clock.
C. All households that have a microwave oven also have either a gas oven or a Conventional electric oven.
D. Households whose microwave oven does not have a built-in clock are no more likely to have a separate electric clock plugged in than households whose microwave oven has one.
E. There are more households that have a microwave oven with a built-in clock than there are households that have a microwave oven without a built-in clock.

Let’s look at the stimulus given-

Premises 
Most household appliances use electricity only when in use. 
Many microwave ovens, however, have built-in clocks and so use some electricity even when they are not in use. 
The clocks each consume about 45 kilowatt-hours per year.

Conclusion 
Therefore, households without a built-in clock microwave use less electricity than households with a built-in clock microwave.

This is an assumption-based question. We need to look for an answer choice that when negated results in breaking the main conclusion that on average the households with no built-in clock microwave use less electricity than the households with no clock microwave.
A – The argument is not about microwave ovens in general. The discussion is about microwaves with clocks and without clocks. Option A is irrelevant to the argument.  Eliminate . 
B – The cost of a microwave is irrelevant.  Eliminate 
C – Having a gas oven or conventional oven is not relevant to the argument.  Eliminate .
D – OA – Let’s negate option D. If households whose microwave does not have a clock use an extra clock then the power consumption for the households with both kinds of microwaves would be the same. This breaks the argument and hence is the right answer.  Correct . 
E – The argument is about the power consumed by types of microwave ovens.  Eliminate .

VerbalBot · Answer

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Most household appliances use electricity only when in use. Many micro

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