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Comment on Toasters, Kettles and Blenders
How is the kettle the least
Good question.
Good question.
Notice that I say "Since kettles APPEAR to be the least expensive"
I say this because we cannot be 100% certain that kettles are the least expensive.
That said, we certainly know that toasters aren't the least expensive. So, we know that either kettles or blenders are the least expensive.
We're told that a blender costs $3 less than twice the price of a kettle.
IF it were the case that a blender costs twice the price of a kettle, then we'd be certain that kettles are the least expensive.
However, once we add in the part that says "a blender costs $3 LESS THAN twice the price of a kettle," we cannot be 100% certain that kettles are the least expensive.
Keep in mind that we aren't required to assign the variable to the smallest value.
The main reason to assign the variable to the smallest value is that this typically makes it easier to assign the other variables.
We could assign the variable to ANY of the 3 prices, and we'd still get the correct answer.
Cheers,
Brent
Hi Brent,
Great post, I think we have an easier solution as well:
Let B = cost of blender
T= cost of toast
K = cost of kettle
T = 3 + 2B = QB
B = 2K -3
We can multiply the second equation with 2 to reach the price of 4 kettles
2B = 4K -6
from here we know 4K = 2B + 6 = QA
QB = T = 3 +2B
QA = 2B +6
From here we can see that QA>QB
That's a great approach.
That's a great approach.
Nice work!
Hi ,
I had approached with numbers.
consider 1 kettle cost =100
blender=2(kettle)-3$
=200-3=197
toaster=2(blenser)+3$
=2*197+3=397
Qa-> 4 kettles cost= 400
Qb-> 1 toaster cost=397
therefore Qa > Qb
Thanks
The correct answer is, indeed
The correct answer is, indeed A, however testing only one set of values can get you into trouble with QC questions.
The problem with the plugging in numbers approach is that testing two sets of values is not enough to answer the question conclusively, UNLESS they yield two different results.
For more on this, start watching at 2:50 of the following video: https://www.greenlighttestprep.com/module/gre-quantitative-comparison/vi...
Cheers,
Brent
In addition for that,
T=3+2b
B=2k-3
Let B=100
T=203
K= 51.50
The cost of 4k = 206
and the cost of 1t=203
A>B
The correct answer is indeed
The correct answer is indeed A.
However, I would be wary of testing just ONE value, as you did in your solution.
Testing ONE possible value will not yield a definitive answer on Quantitative Comparison questions
I cover this at 2:50 in the following video: https://www.greenlighttestprep.com/module/gre-quantitative-comparison/vi...
Doesn’t this question depend
We have:
We have:
QUANTITY A: 4k
QUANTITY B: 4k - 3
If k = 1, we get:
QUANTITY A: 4k = 4(1) = 4
QUANTITY B: 4k - 3 = 4(1) - 3 = 1
Quantity A is greater.
If k = 10, we get:
QUANTITY A: 4k = 4(10) = 40
QUANTITY B: 4k - 3 = 4(10) - 3 = 37
Quantity A is still greater.
In fact, Quantity A will be greater than Quantity B for all values of k.
Does that help?