A man is climbing up a mountain which is inclined

Question

A man is climbing up a mountain which is inclined. He has to travel 100 km to reach the top of the mountain. Every day He climbs up 2 km forward in the day time. Exhausted, he then takes rest there at night time. At night, while he is asleep, he slips down 1 km backwards because the mountain is inclined. Then how many days does it take him to reach the mountain top? I'm in the dire need of math https://helpinhomework.org/math-homework-help.

Answer 1

100 = (2-1) days = 1 km per day for 100 days to reach the top

(2-1)D = 100

D = 100/1 = 100 days

although even he already reaches the top on the 99th day.

but may slip back 1 km that night, so as to need a 100th day

after one day & night he's up 1 km

after two days & two nights he's reached 2 km

after n days and n nights he reaches n kilometers

after 100 days and 100 nights he reaches 100 kilometers

after 99 days and 99 nights he reaches 100 kilometers but may fall back 1 km that night, so he's not on top anymore

answer they probably want is 99 days and nights to reach the top.

that 100th day, if needed, will be the 2nd time he reaches the top.