00:01
In the first question, we're given from a report.
00:04
47 % of female undergrads from a particular university take on debts, and 10 female undergrads were randomly selected.
00:13
Now let x be the number of female undergrads out of these 10 will take on debts.
00:18
Now, since we assume that these 10, they took on or did not take on debts independently, x will follow the binomial distribution, at which end the number of trials is going to be done.
00:32
10 and p probability of success in a single trial there's probability of a female undergrad taking on that there'll be 47 % or 0 .47 in decimal so probability x equals to r where r is the number of female undergrads out of this 10 who took on that that will be then choose r 0 .47 to the power r and 1 minus 0 .470 53 to the power of then minus r now i want to find probability none of the 10 female undergrads took on that.
01:08
So we're looking at probability x equals to 0.
01:11
Just sub 0 into the r answer, which is 0 .002, 3 decimal place.
01:34
Now next, we're given from a report, 11 .1 % of female undergrads from a particular unisity to conducts and 20 female undergrads were randomly selected.
01:48
Let y be the number of female undergrads out of these 20 who took on debts.
01:53
Now again, y follows the binomial distribution and the number of trials will be 20.
01:59
And p, probability of success in a single trial, there is probability of female undergrad due on debt.
02:04
There will be 11 .1 % or 0 .111.
02:09
So probability y equals to r, where r is the number of female undergrads are 20 who took on debts.
02:15
That will be 20 choose r, 0 .1%.
02:18
111 to power r and 1 minus 0 .111 would be 0 .889 to the power of 20 minus r.
02:27
So now we want to find exactly four female undergrads taking on that.
02:33
We want to find the probability of that.
02:35
So we're looking at probability y equals to four.
02:38
So just sub 4 into the r...