The mean of the following distribution is 35. Find the values of x₁ and x₂, if the sum of the frequencies is 25.
Attachments:
Answers
Answered by
1
It is given that ,
Sum of the frequencies = 25
From the table ,
=> Sigma ( fixi ) = 17 + x1 + x2 = 25 ---( 1 )
=> x1 + x2 = 25 - 17
=> x1 + x2 = 8 -----( 2 )
Mean = 35 [ given ]
=> [ Sigma fixi ]/( sigma fi ) = 35
=> ( 605 + 15x1 + 45x2 )/25 = 35
=> 605 + 15x1 + 45x2 = 875
=> 15x1 + 45x2 = 875 - 605
=> 15x1 + 45x2 = 270
Divide each term by 15 , we get
=> x1 + 3x2 = 18 ----( 3 )
Subtracting equation ( 2 ) from ( 3 ),
we get,
2x2 = 10
=> x2 = 5
put x2 = 5 in equation ( 2 ) , we get
x1 = 8 - 5 = 3
Therefore ,
x1 = 3 , x2 = 5
••••
Sum of the frequencies = 25
From the table ,
=> Sigma ( fixi ) = 17 + x1 + x2 = 25 ---( 1 )
=> x1 + x2 = 25 - 17
=> x1 + x2 = 8 -----( 2 )
Mean = 35 [ given ]
=> [ Sigma fixi ]/( sigma fi ) = 35
=> ( 605 + 15x1 + 45x2 )/25 = 35
=> 605 + 15x1 + 45x2 = 875
=> 15x1 + 45x2 = 875 - 605
=> 15x1 + 45x2 = 270
Divide each term by 15 , we get
=> x1 + 3x2 = 18 ----( 3 )
Subtracting equation ( 2 ) from ( 3 ),
we get,
2x2 = 10
=> x2 = 5
put x2 = 5 in equation ( 2 ) , we get
x1 = 8 - 5 = 3
Therefore ,
x1 = 3 , x2 = 5
••••
Attachments:
Similar questions