Daily output of marathon's garyville, lousiana, refinery is normally distributed with a mean of 232,000 barrels of crude oil per day with a standard deviation of 7,000 barrels. (a) what is the probability of producing at least 232,000 barrels?

50% A normal distribution is symmetric about the mean. That means that no matter what the standard deviation of a statistic, if it is normally distributed half of the time it will above the mean and half will be below. 232000 barrels is the mean and half of the time production will be above that value.