Chang has to go to school this morning for an important test, but he woke up late. He can either take the bus or take his unreliable car. If he takes the car, Chang knows from experience that he will make it to school without breaking down with probability 0.4. However, the bus to school runs late 75% of the time. Chang decides to choose betweens these options by tossing a coin. Suppose that chang does, in fact, make it to the test on time. What is the probability that he took the bus? Round your answer to two decimal places.