AP EAMCET201920 Apr 2019Morning ShiftMathematicsStatisticsActual
The variance of the following continuous frequency distribution is ( array lllll Class Interval & 0-10 & 10-20 & 20-30 & 30-40 Frequency & 2 & 3 & 4 & 1 array )
Options
- A201
- B62
- C19
- D84
Correct answer
D. 84
Step-by-step solution
Given ( array llllll array l Class Interval array & array c Frequency ( f _ i ) array & x _ i & x _ i f _ i & ( x - x _ i )^2 & f _ i ( x - x _ i )^2 0-10 & 2 & 5 & 10 & 196 & 392 10-20 & 3 & 15 & 45 & 16 & 48 20-30 & 4 & 25 & 100 & 36 & 144 30-40 & 1 & 35 & 35 & 256 & 256 & N= f_i=10 & & f_i=190 & f_i ( x -x_i )^2=840 array ) ( array ll & x = x_i f_i N = 190 10 =19 Variance ( )^2 & = 1 N f_i ( x -x_i )^2= 1 10 (840)=84 array ) Hence, option (4) is correct.