Math A worm is at the bottom of a forty meter hole. It can crawl upwards at the rate of four meters in one day, but at night, it slips back three meters. At this rate, how long will it take the worm to crawl out of the hole?

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If you find this type of word problem confusing, you might find drawing a picture helpful. I am a very visual learner and I used to draw out this type of problem. Even when I advanced into complicated math, I would still draw a sketch to double check my answers. If you are a hands on learner or a visual learner, drawing a sketch and physically tracing the worms path in the hole can be very helpful to understanding this type of word problem.
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Yes, it is pretty simple.  You solve this by taking the total distance the worm travels and subtracting the amount it slips back.  Four minus three is one.  So it climbs a meter a day, but on the last day it won't slip back and it gets out.  Persistent worm!

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I did the math out and I agree with pohnpei that on day 37, the worm hits the 40 meter mark and should be able to get out of the hole.

Basically, the worm gains one meter per day, because he climbs 4 and slides back 3, and 4-3=1. So the morning of day 37, when the worm begins at 36 meters from the bottom, it will climb the last 4 meters and exit from the hole.

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I think it should take it 37 days.  It should make it out of the hole on the 37th day because it will get out of the hole before night and so it won't slip back.  On day 36, it should get up to 39 meters and slip back to 36 meters in the night.  On day 37, it will go up 4 more meters and get out of the hole.

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