Please explain this with steps thank you

The table below shows the number of one company's stores located in each of 50 regions. Complete parts (a) through (c) below. 567 8 309 129 196 122 69 85 95 115 155 33 36 158 341 137 200 234 25 23 405 143 110 b. What percentage of the 50 regions have stores within 1 1, + 2, or + 3 standard deviations of the mean? The percentage within + 1 standard deviation of the mean is (Type an integer or a decimal. Do not round.) The percentage within + 2 standard deviations of the mean is (Type an integer or a decimal. Do not round.) The percentage within + 3 standard deviations of the mean is (Type an integer or a decimal. Do not round.)