How to Calculate Standard Deviation

&NewLine;<&excl;-- WP QUADS Content Ad Plugin v&period; 2&period;0&period;95 -->&NewLine;<div class&equals;"quads-location quads-ad1" id&equals;"quads-ad1" style&equals;"float&colon;left&semi;margin&colon;0px 0px 0px 0&semi;">&NewLine;&NewLine;<&sol;div>&NewLine;<p> <strong><&sol;strong><&sol;p>&NewLine;<p> <strong>Problem&colon;<&sol;strong> Following are the number of students enrolled in English coaching program each month for the last 7 months 24&comma; 21&comma; 29&comma; 18&comma; 26&comma; 20&comma; and 23&period; Find standard deviation by taking data &lpar;a&rpar; as sample &lpar;b&rpar; as population&period; <&sol;p>&NewLine;<p> &&num;160&semi;<&sol;p>&NewLine;<p> <a href&equals;"http&colon;&sol;&sol;mba-lectures&period;com&sol;wp-content&sol;uploads&sol;2010&sol;06&sol;image84&period;png"><img title&equals;"image" style&equals;"border-top-width&colon; 0px&semi; display&colon; inline&semi; border-left-width&colon; 0px&semi; border-bottom-width&colon; 0px&semi; border-right-width&colon; 0px" height&equals;"506" alt&equals;"image" src&equals;"http&colon;&sol;&sol;mba-lectures&period;com&sol;wp-content&sol;uploads&sol;2010&sol;06&sol;image&lowbar;thumb84&period;png" width&equals;"500" border&equals;"0" &sol;><&sol;a> <&sol;p>&NewLine;<p> &&num;160&semi;<&sol;p>&NewLine;<p> <strong>Calculation of Standard Deviation for Grouped Data<&sol;strong> <&sol;p>&NewLine;<&excl;-- WP QUADS Content Ad Plugin v&period; 2&period;0&period;95 -->&NewLine;<div class&equals;"quads-location quads-ad2" id&equals;"quads-ad2" style&equals;"float&colon;none&semi;margin&colon;0px 0 0px 0&semi;text-align&colon;center&semi;">&NewLine;&NewLine;<&sol;div>&NewLine;&NewLine;<p> &&num;160&semi;<&sol;p>&NewLine;<p> <strong>Problem&colon;<&sol;strong> Following are the observations showing the age of 50 employees working in a whole sale center&period; Find standard deviation by taking data &lpar;a&rpar; as sample &lpar;b&rpar; as population<&sol;p>&NewLine;<p> &&num;160&semi;<&sol;p>&NewLine;<p> <a href&equals;"http&colon;&sol;&sol;mba-lectures&period;com&sol;wp-content&sol;uploads&sol;2010&sol;06&sol;image85&period;png"><img title&equals;"image" style&equals;"border-top-width&colon; 0px&semi; display&colon; inline&semi; border-left-width&colon; 0px&semi; border-bottom-width&colon; 0px&semi; border-right-width&colon; 0px" height&equals;"54" alt&equals;"image" src&equals;"http&colon;&sol;&sol;mba-lectures&period;com&sol;wp-content&sol;uploads&sol;2010&sol;06&sol;image&lowbar;thumb85&period;png" width&equals;"500" border&equals;"0" &sol;><&sol;a> <&sol;p>&NewLine;<p> &&num;160&semi;<&sol;p>&NewLine;<p> &&num;160&semi;<&sol;p>&NewLine;<p> <a href&equals;"http&colon;&sol;&sol;mba-lectures&period;com&sol;wp-content&sol;uploads&sol;2010&sol;06&sol;image86&period;png"><img title&equals;"image" style&equals;"border-top-width&colon; 0px&semi; display&colon; inline&semi; border-left-width&colon; 0px&semi; border-bottom-width&colon; 0px&semi; border-right-width&colon; 0px" height&equals;"438" alt&equals;"image" src&equals;"http&colon;&sol;&sol;mba-lectures&period;com&sol;wp-content&sol;uploads&sol;2010&sol;06&sol;image&lowbar;thumb86&period;png" width&equals;"500" border&equals;"0" &sol;><&sol;a>&NewLine;<&excl;-- WP QUADS Content Ad Plugin v&period; 2&period;0&period;95 -->&NewLine;<div class&equals;"quads-location quads-ad3" id&equals;"quads-ad3" style&equals;"float&colon;none&semi;margin&colon;0px&semi;">&NewLine;&NewLine;<&sol;div>&NewLine;&NewLine;