The easiest way to do this is calculate the probability that all drives crash, and subtract that from one. The first one is .06 squared subtracted from 1, so it’s .9964 or 99.64%. The second one is .06 cubed subtracted from 1, so it’s .9998, or 99.98 %
You have to have intelligence to make achievements. Because you must have a strategy plan to get the achievement