Answer :
To calculate the probability of going through at least one red light when driving through two lights, you can use the concept of complementary probability, which is 1 minus the probability of not encountering any red lights.
Here's how you can approach the problem:
1. **Identify the Possible Outcomes**:
- When driving through two lights, there are 4 possible outcomes: RR (both red lights), RG (first red, second green), GR (first green, second red), GG (both green lights).
2. **Calculate the Probability of Not Going Through any Red Light**:
- The outcomes without encountering any red lights are GG (both green lights).
- Therefore, the probability of not encountering any red light is 1/4.
3. **Calculate the Probability of Going Through at Least One Red Light**:
- The probability of going through at least one red light is the complement of not encountering any red lights.
- Hence, it is 1 - 1/4 = 3/4 or 75%.
Therefore, when driving through two lights, the probability of going through at least one red light is 75%.
You can also represent this using a tree diagram or by listing out all the outcomes. This approach allows you to visualize the possibilities and understand the concept of complementary probability in a practical way.
