another probability question

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anteater85

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Five hours after sasha began walking from A to B, a distance of 100 miles, Mario started walking along the same road from B to A. If Sasha's walking rate was 2 miles per hour and Mario's was 3 miles per hour, how many miles had Mario walked when they met?

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I don't think this is a probability question, but anyways...

Combine the two rates.

2mph + 3mph = 5mph

Divide the total distance by the combined rate.

(100miles)/(5miles/hour) = 20 hours [miles cancel]

Multiply that 20 hours by the 3mph (Mario's speed).

20 hours x 3miles/hour = 60 miles [hours cancel]
 
It should be 18 hours * 3 mph, because Sasha had already walked 5 hours at 2 mph (covered 10 miles) and 100 total miles minus 10 miles = 90 miles. 90 miles/5 mph= 18 hours and Mario would walk 3 mph per 18 hours.
 
It should be 18 hours * 3 mph, because Sasha had already walked 5 hours at 2 mph (covered 10 miles) and 100 total miles minus 10 miles = 90 miles. 90 miles/5 mph= 18 hours and Mario would walk 3 mph per 18 hours.

Pfff, details :laugh:
 
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Nevermind read the question wrong haha.

Ignore my last post.

I saw that Mario walked from A to B when he actually walked B to A. :)

Answer is 54.
 
Last edited:
I think cheerio is right.

Sasha has gone 10 miles by the time the other dude starts so there 90 miles apart. She travels 2/5 of the 90 miles to meet him and he travels 3/5 of the 90 miles to meet her. 3/5 of 90 is 54.
 
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