A company wants to determine whether their workers can opera

A company wants to determine whether their workers can operate a machine’s emergency shutoff device. It was found in the testing run that 65% were successful with their left hands, 92% with their right hands, and 49% with both hands. (a) What percent of their workers could not operate the device with either hand? (b) What is the probability that a randomly selected worker could operated the device with both hands, given that he/she was successful with the right hand? (c) What is the probability that a randomly selected worker could operated the device with both hands, given that he/she was successful with the left hand?

Solution

alright, so the pr(right)=.92, pr(left)=.65 and pr(right AND left)=.49
I think the easiest way to go about part a is to draw a venn diagram. two circles representing the left and right, where the interconnected space has the value of .49

Now if the middle portion of the venn is .49 and we know that the entire left is .65, then the value of the left circle is .65-.49=.16

Same thing with the right side, the middle is .49 and the middle and right are together .92 therefore the right only is .92-.49=.43

So if .16+.43+.49=.108 This gives that 108% of the workers are capable.

Maybe the percentage of the workers are wrong.. you should check them..