00:01
We have some information and i'm going to write it in probability notation.
00:05
So last year, 10 % of employees had lost time accidents.
00:10
So the probability of last year having an accident is 10%, 0 .1.
00:17
However, a special safety program has brought that down to 4 % in the current year.
00:22
So probability of getting such an accident in the current year is only 4%.
00:27
It is estimated that 15 % of employees who had an accident last year will get one this year.
00:35
So the probability of getting an accident in the current year, given there was one in the last year, is 15%.
00:42
So we've got this conditional probability.
00:45
In general, it's 4%, but for the ones who had an accident last year, it's higher than that.
00:51
So first part, what percentage will experience lost time accidents in both years? i could write that as the probability of last year and current year.
01:04
Now i've got a formula for conditional probability to help me here.
01:08
The probability of x given y, multiplied by the probability of y, is the intersection x and y.
01:16
So for this, i need current given last, multiplied by last...