The source of the error when a computer system fails are either the disk drive, the computer memory, or the operating system. Very often, 55% of the errors are disk drive errors, 32% are computer memory errors, and the remainder are operating system errors. From the component performance standards, the probabilities of failure due to disk drive, computer memory, and operating system errors are 0.65, 0.6 and 0.25, respectively. Given the information from the component performance standards, what is the probability of an operating system error, given that a failure occurred?