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Question 932678: The volume of first cylinder is 12m^3. Second cylinder height is 3 time longer and base radus 2 times shorter than first cylynder parameters. Please, calculate the second cylinder volume.
A. 6.0m^3 B. 6.5m^3 c. 9.0m^3 D. 5.5m^3 E.7.5m^3
Found 5 solutions by mananth, greenestamps, josgarithmetic, ikleyn, Alan3354:
Answer by mananth(16946)   (Show Source):
You can put this solution on YOUR website!
The volume of first cylinder is 12m^3.
pir^2h = 12
Second cylinder height is 3 time longer and base radus 2 times shorter than first cylynder parameters.
pi* (r/2)^2*(3h) =V
pi*(r^2/4)*3h= V
V/12= pi*(r^2/4)*3h/pir^2h
v/12 =3/4
V= 12*3/4 = 9 m^3
Answer by greenestamps(13216)  (Show Source):
You can put this solution on YOUR website!
The author of this problem uses improper sloppy language which has no place in a serious math problem.
The other tutor interprets the given statement that the second cylinder is 3 time (sic) longer than the first cylinder to mean that the length of the second cylinder is 3 times the length of the first; and she interprets the statement that the base radus (sic) of the second cylinder is 2 times shorter than the base radius of the first cylinder to mean that the base radius of the second cylinder is 1/2 the base radius of the first cylinder.
Those interpretations are almost surely what the author of the problem intended; however, neither of those interpretations is grammatically correct. The second statement is in fact total nonsense.
If the length of the first cylinder is x, then the length of the second cylinders is 3x IF IT IS 3 TIMES AS LONG AS the first cylinder.
But if the length of the first cylinder is x and the second cylinder is 3 TIMES LONGER THAN the first, then the length of the second cylinder is x, PLUS 3 more times x -- or x+3x, which is 4x.
So "3 times longer than" means "4 times as long as".
Unfortunately, in sloppy everyday language, "3 times as long as" and "3 times longer than" are used (incorrectly!) to mean the same thing.
The given statement about the radius of the second cylinder is total nonsense. In everyday language, "2 times shorter than" is sloppily used to mean "1/2 as long as". But the grammatically correct interpretation of "2 times shorter than" is nonsensical.
If the radius of the first cylinder is y and the radius of the second cylinder is "2 times shorter than" the radius of the first, the correct interpretation of that statement is that the radius of the second cylinder is y, MINUS 2 times y -- which gives y-2y = -y....
A negative number for the radius of the second cylinder is absurd....
Presumably, you have shown the problem exactly how it was given to you, so my comments are not directed to you but rather to the author of the problem.
However, you have the unfortunate task of trying to guess what the given information really means....
Answer by josgarithmetic(39630)  (Show Source):
Answer by ikleyn(52921)  (Show Source):
You can put this solution on YOUR website! .
Obviously, this post is a translation from other language,
but the person who translates it, does not know the standard rules
of presenting such problems in English (did not open and
did not read Math textbooks for middle schools in English).
It is a typical mistake of newcomers who start using English.
My advise to the translator/composer:
In the Google search engine print
" three times longer versus three times as long "
and read the info which Google will provide in response
https://forum.wordreference.com/threads/three-times-longer-than-three-times-as-long-as.1909017/
For other similar possible forms, print their analogs in Google again and learn
the responses from Google.
Doing this way, you will learn how not to fall into this trap in the future.
Answer by Alan3354(69443)  (Show Source):
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