Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

James lives in San Francisco and works in Mountain View. In the morning, he has 3 transportation options (bus, cab, or train) to work, and in the evening he has the same 3 choices for his trip home.
If James randomly chooses his ride in the morning and in the evening, what is the probability that he'll take the same mode of transportation twice?

James lives in San Francisco and works in Mountain View. In the morning, he has 33 transportation options (bus, cab, or train) to work, and in the evening he has the same 33 choices for his trip home.\newlineIf James randomly chooses his ride in the morning and in the evening, what is the probability that he'll take the same mode of transportation twice?

Full solution

Q. James lives in San Francisco and works in Mountain View. In the morning, he has 33 transportation options (bus, cab, or train) to work, and in the evening he has the same 33 choices for his trip home.\newlineIf James randomly chooses his ride in the morning and in the evening, what is the probability that he'll take the same mode of transportation twice?
  1. Question Prompt: question_prompt: What's the chance James takes the same ride to and from work?
  2. Total Combinations: He's got 33 options for the morning and 33 for the evening, so total combinations for both trips are 3×33 \times 3, which is 99.
  3. Same Mode Options: For taking the same mode twice, he can choose bus-bus, cab-cab, or train-train. That's 33 ways he can do that.
  4. Probability Calculation: So the probability is the number of ways he can take the same mode over the total combinations, which is 39\frac{3}{9}.
  5. Simplification: Simplify 39\frac{3}{9} to 13\frac{1}{3}, cuz both are divisible by 33.

More problems from Find probabilities using the addition rule