Carson drives to school the same way each day and there are two independent traffic lights on his trip to school. he knows that there is a 30% chance that he will have to stop at the first light and an 80% chance that he will have to stop at the second light. determine the probability that he will not have to stop at either light.

Thank you for posting your question. I hope you found you were after. Please feel free to ask me another.

Hence, the probability is:

                        0.14   or   14%

Let A  denote the event that he stop at the first light.

and B denote the event that he stops at the second light.

Let P denote the probability of an event.

Also, we are given that:

There is a 30% chance that he will have to stop at the first light.

i.e.

P(A)=30%=0.30

and

80% chance that he will have to stop at the second light.

i.e.

P(B)=80%=0.80

Now, we are asked to find:

The probability that he will NOT have to stop at either light.

i.e. we are asked to find:

Also, the events A complement and B complement will be independent.

Hence, we get:

Based on the data we have:

Hence, we get:

i.e.

which in percent is: