Question 1145115: Today Peter is 20 years old and James is 6 years old. In how many years from today would Peter be 2 times older than James ?
A)18
B)12
C)8
D) non of these
My answer is D
Found 3 solutions by greenestamps, Alan3354, ikleyn:
Answer by greenestamps(13200)   (Show Source):
You can put this solution on YOUR website!
Your answer is in fact correct.
However, it is likely that the author of the problem wanted C as the answer.
The reason for that is that the language used to present the problem is incorrect.
How the problem was probably intended to be worked....
(1) The difference in their ages is 14 years.
(2) When Peter is "2 times older than James" their ages will be 14 and 28.
(3) Since they are now 6 and 20, that will be 8 years from now.
ANSWER C
The trouble with that solution is that it does not correctly interpret the given information. Specifically, "2 times older than" is NOT the same as "2 times as old as".
If one person's age is x and another person is 2 TIMES AS OLD, then the other person's age is 2x. That makes the difference in their ages 2x-x = x.
But if one person's age is x and another person is 2 TIMES OLDER, then the other person's age is x plus 2x, which is 3x. That makes the difference in their ages 3x-x = 2x.
So to solve the problem as written, the correct solution is as follows....
(1) The difference in their ages is 14 years.
(2) When Peter is 2 times OLDER THAN James -- i.e., 3 times AS OLD as James -- their ages will be x and 3x, a difference of 2x; since the difference in their ages is 14, 2x=14 gives us x=7, which makes their ages 7 and 21.
(3) Since they are now 6 and 20, that will be 1 year from now.
ANSWER D
Answer by Alan3354(69443)  (Show Source):
You can put this solution on YOUR website! 2 times older is not the same as 2 times as old.
Is 1 time older the same age? If so, why say "older?"
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"3 times smaller" makes no sense, since 1 time smaller is zero (0).
5 times closer makes no sense, since 1 time closer is coincident, the same place.
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People who don't understand the subject should not attempt to write math problems.
Or anything else.
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Is 1 time older the same age? If so, why say "older?"
In any language?
Eschew obfuscation.
Answer by ikleyn(52781)  (Show Source):
You can put this solution on YOUR website! .
Alan, it is only in English "two times older than . . . " means "three times as old as . . . ". (1)
In all OTHER languages, as far as I know, "two times older than . . . " means the same as "two times as old as . . . " (2)
Even in EVERYDAY English the statement (2) is used as valid.
Therefore, when you see this mistake in the post, simply explain it to the author and react on it with understanding.
/\/\/\/\/\/\/\/\/\
In Great Britain, after using feet, yards, pounds and so on during HUNDREDS years, they, finally, changed their
archaic measuring system to the modern one.
I am sure, that in the future REFORM of English, they will exclude all articles for their absolute useless,
as well as will exclude the form "three times as old as" as archaic,
replacing it by "three times older than", as it works in all other languages.
(You may consider it as a joke, or as a true prediction - on your choice).
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