Calculate the arithmetic mean and standard deviation of the following values:

(i) without grouping

(ii) grouping the value in classes 140–145, 145–150 .............

(iii) grouping them in classes 140–150, 150–160 ............

140	143	143	146	146
146	154	156	159	162
164	174	166	166	167
167	168	168	169	169
169	171	175	175	176
176	178	180	182	182
182	182	182	183	184
186	188	190	190	191
191	192	195	202	217