It's climbing five feet per day, but would loose three feet at the end of every night Which sums up to 2fts/day. It should take a snail total 15 days to reach.
A most submarines are basically circular, so you would have to calculate the circumference of the submarine first, then determine half of the diameter, and that is how far it would have to climb, provided that it is starting at the very bottom. If the diameter is 30 feet, to find the circumference, we multiply the diameter by pi (3.14), then divide by two to get the distance the snail would travel (47.1 ft), then divide this by the two feet of progress the snail makes in one day. Answer = he reaches the top about halfway through the 24th day
The answer is 22 days. Using the prior answerers correct circular calculation: "A most submarines are basically circular, so you would have to calculate the circumference of the submarine first, then determine half of the diameter, and that is how far it would have to climb, provided that it is starting at the very bottom. If the diameter is 30 feet, to find the circumference, we multiply the diameter by pi (3.14), then divide by two to get the distance the snail would travel (47.1 ft), " We get the most accurate measure short of using calculus that will approximate the length of the side of a circular submarine whose height is 30 ft. Rather than perform the simple arithmetic of dividing by 2 we know that the snail is not going to continue dropping after it has reached the top. Therefore at the end of the 21st day we can see that the snail will reach 45 ft by assuming 2 feet every night and day combined for 20 periods plus 5 ft more for day 21 [(5-3)*20+5)=45]. The snail is still 2.1 feet short of its goal before sliding back 3 ft that night. Then on the 22nd day the snail starts at 42 feet. At the end of the day he will get to 47 feet. You may say that with .1 ft to go the snail will not have reached its goal and will need part of another day to summit the submarine. Its a fair assumption and hard to argue with. In that case you would say the answer is 23.62 days ([(5ft-3ft)*23days+3.1ft/5ft per day)=47.1 days. I prefer to assume that the snail will see that the end is near and cross the last .1 ft at the end of the 22nd day knowing that the reward for a little extra effort is going to be a night's sleep to avoid the significant loss of 3 ft that night. Who stops for the night when the goal is right there to be had with a little extra effort? I wouldn't. The importance of this question is not necessarily which "final" measurement in days is selected but on how logical (and possibly how creative) the thought process, assumptions and conclusion are. There is no "right" answer to this question. A question such as this may be used to determine attributes such as the ability to work and think under pressure, intellect, attention to detail, creativity, and ability to communicate.
it never says where the snail is starting the climb from .... that information has to be given first or everything else is an assumption
