17P5/75
Five persons entered the lift cabin on the ground floor of an 8-floor house. Suppose that each of them independenly and with equal probability can leave the cabin at any floor beginning with the first. Find the probability of alll five persons leaving at different floors.
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5 Answers
4P = selecting 1 person for each floor / total case
= 7P5 / 7^5
7^5 becz each person has a chance of selecting out of 5 floors
3Well...actually Kaymant sir helped me out with this one....
There are 5 persons....and each one can come out in 8 ways..1st floor....2nd floor....8th floor.So no.of ways = 85
And the total no of ways = 8P5.
Therefore the ans should be...=8P585
4@ swastika : Mine wud be correct if u considered ground floor as 1st one & 7 more floors
They wont get down at grd floor na!!
Otherwise ya u're ans is correct :)