dhritidutta wrote:
Mike has been biking through the Rockies for 2 days and has used up 4/9 of his medication. If the only way for him to get more medication is to return to his starting point, how much longer can he bike before he has to turn around and ride back to his starting point along the same path?
A. 1/36 day B. 1/18 day C. 1/9 day D. 1/4 day E. 1/2 day
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In 2 days, Mike uses = 4/9 of his meds
To return, he needs 1/2 of his meds left on him.
Therefore, he needs = 1/2 * 9/9 = 4.5/9 to make the return trip
Thus, he can use another 0.5/9 unit (i.e. 4.5/9 - 4/9)
Since he uses 4/9 in 2 days
he'll use 0.5/9 in = 2/(4/9) * 0.5/9 = 2/4 * 0.5 = 1/4 day
He has 1/4 day left before he has to turn around.
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