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655-705 (Hard)|   Assumption|      
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Bunuel
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­Electrical engineers have developed an energy-efficient type of light 20 Jul 2026, 19:00
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55% (hard)

Question Stats:

58% (01:51) correct 42% (01:55) wrong based on 368 sessions

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­Electrical engineers have developed an energy-efficient type of light bulb that can replace the traditional incandescent bulb. The new bulb, known as the electronic lamp, operates by using a high frequency radio signal rather than the filament featured in incandescent bulbs. Although the electronic lamp currently costs 20 times as much as its traditional counterpart, its use will prove more cost effective in the long run. While a 100-watt incandescent bulb lasts 6 months if burned for 4 hours daily, a 25-watt electronic lamp used for the same amount of time each day lasts up to 14 years.

The argument above assumes that

A. the typical household use of a light bulb is approximately 4 hours a day

B. aside from its greater efficiency, the electronic lamp resembles the incandescent light bulb in most aspects

C. the type of light cast by the electronic lamp is different from that cast by an incandescent bulb

D. the price of electronic lamps will decrease as they are produced in increasingly greater quantities

E. a 100-watt incandescent light bulb does not provide significantly more light than a 25-watt electronic lamp


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E
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­Electrical engineers have developed an energy-efficient type of light 21 Jul 2026, 04:11
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A. The 4-hour figure is just used to make a fair comparison. The argument doesn't depend on how long people typically use a light bulb.
B. Whether the bulbs are similar in other ways isn't important. The claim is about long-term cost, not overall design.
C. The argument never assumes the light looks the same. It's comparing cost, not the color or quality of the light.
D. The conclusion is based on today's prices. It doesn't require the electronic lamp to become cheaper later.
E. Correct For the electronic lamp to truly replace a 100-watt incandescent bulb, it has to provide roughly the same amount of light. Otherwise, the cost comparison isn't really apples to apples.
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Vihangoyal12345
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­Electrical engineers have developed an energy-efficient type of light 21 Jul 2026, 05:08
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E is correct as whole conclusion depend on it a is distractor as we neglect a our conclusion not weak
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­Electrical engineers have developed an energy-efficient type of light 21 Jul 2026, 08:02
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The argument here is that the energy efficient light bulb can replace the traditional incandescent bulb. Think of it in terms of an LED that we generally use in modern times.
This energy efficient bulb costs 20 times as much the traditional incandescent bulb but in the long run will be cost effective. It will last longer than the traditional bulb.

We are asked to find an assumption in this argument. Let's do a bit of pre-thinking before we jump to the answer choices. Why would a person buy an expensive 25 watt energy efficient bulb over a cheaper 100 watt bulb. On what parameter other than the can they be compared? Is it possible that a 25 watt energy efficient electronic lamp gives the same amount of light or brightness if not more?

A. The 4 hr usage is an example and has nothing to do with the avg household usage of the bulb, ignore it.
B. Okay, it might resemble the incandescent bulb in most aspects but what? too broad of an assumption
C. Even if the light cast is different (one yellow and one white) people might still buy them for different purpose. Not a necessary assumption.
D. WE do not have to bother about the long term price and production of it right now. LEDs we even costly initially but now they have become cheaper.
E. It says the 100 watt incandescent bulb does not provide significantly more light than a 25 watt electronic lamp. This is where the energy efficient assumption is required that a lower watt bulb will give the same amount of light a 100 watt bulb.

Hence, option E is the assumption here that is needed.
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­Electrical engineers have developed an energy-efficient type of light 26 Jul 2026, 03:00
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Bunuel
­Electrical engineers have developed an energy-efficient type of light bulb that can replace the traditional incandescent bulb. The new bulb, known as the electronic lamp, operates by using a high frequency radio signal rather than the filament featured in incandescent bulbs. Although the electronic lamp currently costs 20 times as much as its traditional counterpart, its use will prove more cost effective in the long run. While a 100-watt incandescent bulb lasts 6 months if burned for 4 hours daily, a 25-watt electronic lamp used for the same amount of time each day lasts up to 14 years.

The argument above assumes that

A. the typical household use of a light bulb is approximately 4 hours a day

B. aside from its greater efficiency, the electronic lamp resembles the incandescent light bulb in most aspects

C. the type of light cast by the electronic lamp is different from that cast by an incandescent bulb

D. the price of electronic lamps will decrease as they are produced in increasingly greater quantities

E. a 100-watt incandescent light bulb does not provide significantly more light than a 25-watt electronic lamp
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­

KAPLAN OFFICIAL EXPLANATION:



E

Here we need to identify an assumption. The author attempts to demonstrate that the "electronic lamp" can replace the incandescent bulb (that's the conclusion) because although the electronic lamp now costs much more, it will prove more cost effective in the long run (that's a summary of the evidence). He backs up this claim with numbers: A 25-watt electronic lamp can last 28 times longer than a 100-watt incandescent bulb while costing only 20 times as much as the bulb (thaT's the-hard evidence). There's one factor missing from the equation, though, and that's the amount of light the electronic lamp supplies. For the numbers given to support the author's conclusion, the electronic lamp and the normal bulb must each throw about the same amount of light. Otherwise, we might need 15 lamps for every bulb; and if this were the case, the argument would be dead wrong. Unless we assume, as (E) says, that the light produced by the lamp and the bulb is approximately equal, the evidence is meaningless.

(A) isn't assumed because the figure 4 hours a day doesn't have to represent typical household use; it need only provide a standard by which the lights can be compared. (B) is contradicted by the author. Since the electronic lamp operates by radio waves instead of a filament, it's clear that there are important structural aspects in which it differs from incandescent bulbs. (C) would actually make us doubt the reasonableness of the author's conclusion, so clearly it isn't assumed. If the electronic lamp is supposed to be a replacement for the incandescent bulb, its light should be similar to that produced by the bulb. (D) misconstrues why the electronic lamp is claimed to be cost effective in the long run-the point is that it lasts longer, not that it will become cheaper. The author is arguing that current electronic lamps are more cost effective, not that future lamps will be.­
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