the frog jumps 3 meters in one day and by the beginning of the next day he is down 2 meters. at the bigginning of the 28th day he is at 28 meters. his hind legs (see hint) goes up 3 meters each day, and his hind legs have to clear the top of the well. 28 + 3 = 31. it couldn't be 27 days b/c the well is exactly 30 meters and his hind legs couldnt clear it.
Well John, it actually takes 28 days and 27 nights, but you have to pay close attention to the wording to pick that up. It depends on what you mean by "day" as well. If you mean a full 24-hour period, then no it doesn't quite take 28 days, but rather 27.5. Furthermore, if you don't start counting days until the frog makes his first jump (which I think is the way to do it anyway), then it is exactly 27 days after all.
at the start of day 1 he is at 0 and jumps to 3 metres
at the start of day 2 he is at 1 and jumps to 4 metres
at the start of day 3 he is at 2 and jumps to 5 metres
etc. etc.
at the start of day 28 he is at 27 and jumps 3 metres to the top and climbs out
he has to make 28 jumps and at one jump per day that will always be 28 days NOT 27
Depends on how you count a day like said by kilroy
i counted it like
at the start of day 0 he is at 0 and jumps to 3 metres
at the start of day 1 he is at 1 and jumps to 4 metres
at the start of day 2 he is at 2 and jumps to 5 metres
etc. etc.
because on his first jump he may have been down the well a matter of seconds which isnt a day at all
The frog can jump 3 meter but while sleeping he slipps 2. The 27th day he had jumped 27 meters. He can jump 3 meters, the well is 30 meters high so its simple math -.- 30-27=3
he can jump 3 meters @ once :o
AND in the 27th day he barely REACHED the 27 meters he didnt start with 27 meters and the day you start doing something never counts as day 0 its counted as day 1
thats why its 28 not 27, word problem and simple math
27th day will only clear him 27 metres...do the math
28 days no more
Day 1 he jumps 3 metres falls back 2 metres = (Day 1, 3 - 2 = 1) follow with me
(Day 1, 3 - 2 = 1)
(Day 2, 3 - 2 = 2)
(Day 3, 3 - 2 = 3)
(Day 4, 3 - 2 = 4)
(Day 5, 3 - 2 = 5)
etc., etc.,
(Day 25, 3 - 2 = 25)
(Day 26, 3 - 2 = 26)
(Day 27, 3 - 2 = 27) on day 28 he is already up 27 metres and his last jump will give him and additional 3 metres and clear him out of the well.
The question is confusing because you ask "how many days". You should ask "how many jumps".
Suppose the well is 3m. With one jump the frog comes out. Took him zero day to come out if you consider that he starts jumping right away. But took him one day if you consider that he has to rest one day before the first jump.
On the 27th day he can just hop right on out and not slide down any more. but you know what stupid to me (and i know this problem is not real life)is that frogs always can jump more than three times a day.
actually, the frog is at 1 meter only after day 1, starting day 2. to chart it, day 1, no of meters=0.
so, on the 27th day, the frog wakes up at the 26 meter mark. it jumps to 29, slides down back to 27.
28th day. frog wakes up to 27 meter mark. makes the jump then goes out.
28th day. so, just 27 days.
unless you consider Day 1 of anything to have spent that day already.
(ex. hey, this is my first day of work. "How many days have you been working?" Uhm.. right?
at the start of day 2 he is at 1 and jumps to 4 metres
at the start of day 3 he is at 2 and jumps to 5 metres
etc. etc.
at the start of day 28 he is at 27 and jumps 3 metres to the top and climbs out
he has to make 28 jumps and at one jump per day that will always be 28 days NOT 27
at the start of day 0 he is at 0 and jumps to 3 metres
at the start of day 1 he is at 1 and jumps to 4 metres
at the start of day 2 he is at 2 and jumps to 5 metres
etc. etc.
because on his first jump he may have been down the well a matter of seconds which isnt a day at all
How long would it take to escape from a well of 3 metres? You shout 'go', the frog jumps, he escapes. Zero days. Not one.
How long would it take to escape from a well of 4 metres? One jump immediately and one in 24hrs time. One day. Not two.
The answer of 28 assumes he sits around and does nothing for the first day, but there's nothing that states that.
he can jump 3 meters @ once :o
AND in the 27th day he barely REACHED the 27 meters he didnt start with 27 meters and the day you start doing something never counts as day 0 its counted as day 1
thats why its 28 not 27, word problem and simple math
Day 1 he jumps 3 metres falls back 2 metres = (Day 1, 3 - 2 = 1) follow with me
(Day 1, 3 - 2 = 1)
(Day 2, 3 - 2 = 2)
(Day 3, 3 - 2 = 3)
(Day 4, 3 - 2 = 4)
(Day 5, 3 - 2 = 5)
etc., etc.,
(Day 25, 3 - 2 = 25)
(Day 26, 3 - 2 = 26)
(Day 27, 3 - 2 = 27) on day 28 he is already up 27 metres and his last jump will give him and additional 3 metres and clear him out of the well.
Suppose the well is 3m. With one jump the frog comes out. Took him zero day to come out if you consider that he starts jumping right away. But took him one day if you consider that he has to rest one day before the first jump.
so, on the 27th day, the frog wakes up at the 26 meter mark. it jumps to 29, slides down back to 27.
28th day. frog wakes up to 27 meter mark. makes the jump then goes out.
28th day. so, just 27 days.
unless you consider Day 1 of anything to have spent that day already.
(ex. hey, this is my first day of work. "How many days have you been working?" Uhm.. right?