BdMO Online Forum

Now you are in 1st floor. You have to go 7th floor. You are able to cross three
floors at a stretch. Then you need to eat a chocolate. There are 3 chocolates for
you in 2,3 and 5th floor. How many different ways you can go 7th floor?

We will solve it in backwards, if we are i 7th floor we can come down to 6th,5th and 4th floor.There is chocolate in only 5th floor so we must come down to 5th floor.From 5th floor we can come down to 4th,3rd and 2nd floor as there is no chocolate in 4th floor we can come down to either 2nd or 3rd floor.From 2nd floor we have to come down to 1st floor.From 3rd floor we can come down either 3rd to 2nd to 1st or 3rd to 1st floor. So total way is 3.

Thanks for sharing...

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