We will use the empirical rule. For a standard normal distribution the mean is equal to 0 and the standard deviation is equal to 1. Then, between 3 standard deviations below the mean, we have 2.35% + 13.5% + 34% = 49.85% of data, and 1 standard deviation above the mean we have 34% of data. Therefore, the percentage of data that are between 3 standard deviations below the mean and 1 standard deviation above the mean is 49.85%+34% = 83.85%.