help needed?

Question

it is known that25 percent of a planet's surface area is land and 75 percent is water.if 5 meteors are heading towards planet,what is probability that all miss and crash in water?design and describe a simulation to determine probability using 2 coins.
can anyone help me understand the question it was on my quiz and i failed it .how is this question solved

Answer 1

Mark is correct. The chance that all 5 will hit water in .75x.75x.75x.75x.75 or 3 to the 5th over 4 to the 5th. The two coin thing could be coin one: 50:50 water/heads and water-land/tails, and for all water(heads) you already have your answer but for all water-land(tails) you must flip the second coin to water/heads and land/tails. This should then generate a 75:25 water/land algorithm.

Answer 2

The odds of any one meteor hitting land is 3:1 against.

And, guess what, the odds of the second meteor hitting land is also 3:1 against. In probablity, event do not "remember" the odds of any one throw of a coin is being heads is even, no matter how many heads or tails you have thrown before, so the ods of any one meteor hitting land is 3:1 against.

However, with 5 meteors the odds that none will hit land is 3:5 against, or 60% that at least one will hit land.

Or, the odds are only 40 out of 100 that all will hit the water.

Answer 3

if a given meteor can come from different diretions, each, has a 25% chance of landing on land and 75% chance of landing in water
as there are 5
thr probability of 1 landing in water is 3/4
the probability of 2 landing in water is 3/4 x 3/4
etc
the probability of all 5 landing in water is 3/4 x 3/4 x 3/4 x 3/4 x 3/4

Answer 4

With 5 meteors the odds that none will hit land is 3:5 against, or 60% that at least one will hit land. The standered is 3:1.