AP EAMCET201922 Apr 2019Morning ShiftMathematicsStatisticsActual
The mean deviation about the mean for the following data ( array llllll Marks obtained & 0-10 & 10-20 & 20-30 & 30-40 & 40-50 Number of Boys 6 & 8 & 10 & 4 & 2 array ) is
Options
- A9.33
- B5.6
- C8.33
- D9.6
Correct answer
D. 9.6
Step-by-step solution
Calculation of mean deviation about mean ( array cccccc array c Marks obtained array & x _ i & f _ i & f _ i x _ i & | x _ i - 2 1 | & f _ i | x _ i - 2 1 | 0-10 & 5 & 6 & 30 & 16 & 96 10-20 & 15 & 8 & 120 & 6 & 48 20-30 & 25 & 10 & 250 & 4 & 40 30-40 & 35 & 4 & 140 & 14 & 56 40-50 & 45 & 2 & 90 & 24 & 48 & array c N= f_i =30 array & array c f_i x_i =630 array & & array c f_i x_i-21 =288 array array ) Mean ( gathered x = f_i x_i f_i = 630 30 =21 Mean deviation = 1 N f_i |x_i-21 | = 288 30 =9.6 gathered )