00:02
Let t be that time at which he must have to leave home.
00:22
So, he reach station a, station a time t added to 0.
00:33
So, if he is on time, for 90 % of time we have p n bracket t subtracted from t added to 10 is greater than equal to 1 which is equal to 0 .90 because n t2 subtracted from t1 be the number of train in the interval t2, t1.
01:34
So, it is equal to 1 subtracted from p n bracket t subtracted from t subtracted from 0 is less than 1 which is equal to 0 .90.
01:54
So, p n, t subtracted from t subtracted from 10 is equal to 10 sorry is equal to 0 which is equal to 0 .10 subtracted from alpha sorry a t equal to e to the power minus alpha t subtracted from t subtracted from 10.
02:24
Where? alpha, t subtracted from, t subtracted from 10 to the power 0 divided by 0 is equal to 0 .10, to the power minus alpha, t subtracted from, t subtracted from 10 is equal to 0 .1 which is equal to minus alpha, t substracted from, t subtract from 10 is equal to e log 0 .10 is equal to minus 2 .30, alpha is equal to 1 divided by 8 train per minute because it is equal to t subtracted from, t subtracted from 10 is equal to 2 .30 divided by 8 alpha which is equal to 8 multiplied by 2 .30.
03:31
So it is equal to t subtracted from, t subtracted from 10 is equal to 18 .4 is equal to t subtracted from t is equal to 28 .4 minutes...