Question 793048: Kat spends 30 minutes of time partly in listening to her professor and partly in text messaging her close friends. The time she spends on text messaging is 2 times more than what she spends listening to her professor. How many minutes does Kat spend listening to her professor?
Found 2 solutions by mananth, greenestamps:
Answer by mananth(16946)   (Show Source):
You can put this solution on YOUR website! Kat spends 30 minutes of time partly in listening to her professor and partly in text messaging her close friends. The time she spends on text messaging is 2 times more than what she spends listening to her professor. How many minutes does Kat spend listening to her professor?
Let her listen to the professor for x minutes
The time she spends on text messaging is 2 times more than what she spends listening to her professor. How many minutes does Kat spend listening to her professor?
2x = 2x hours
2x+x = 1/2 hour
3x = 1/2
x= 1/6 hours =10 minutes
Answer by greenestamps(13200)  (Show Source):
You can put this solution on YOUR website!
The answer shown by the other tutor is very probably the intended answer to the problem. However, it is the wrong answer, because very probably the problem was written incorrectly.
Any math problem written using any form of a phrase like "2 times more than" is an invalid problem, because nearly everybody interprets that phrase incorrectly.
If I spend 2 TIMES AS MUCH time on one task as I do on another, then the amount of time I spend on one task can be represented by x, and the time I spend on the other task can then be represented as 2x.
But if I spend 2 TIMES MORE on one task as I do on another, and the amount of time I spend on the shorter task is x, then the amount of time I spend on the longer task is the amount of time I spend on the shorter task, PLUS 2 TIMES MORE that amount of time -- i.e., x + 2x = 3x.
In everyday sloppy language, "2 times as much as" and "2 times more than" are used to mean the same thing, but they do not.
With the grammatically correct interpretation of the question as written....
x = amount of time spent listening to her professor
3x = amount of time spent text messaging
The total time is 30 minutes:
(correct) ANSWER: Kat spends 7.5 minutes listening to her professor
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