The test score (X) of the training participants has a normal distribution with an average value of 200 and a standard deviation of 50. Participants are declared passed if they get a score > 300 and those who have a score of 200-300 are given a retest. To get the percentage of participants who passed or who were given a retest, it can be known through the standard normal distribution Z. It is known that P(Z < 0)=0.5000 and P(Z < -2.0) = 0.0228. The percentage of the number of participants who took the retest was