Mean and standard deviation of 100 observations were found to be 40 and 10, respectively. If at the time of calculation two observations were wrongly taken as 30 and 70 in place of 3 and 27 , respectively, find the correct standard deviation.

Mean and standard deviation of 100 observations were found to be 40 and 10, respectively. If at the time of calculation two observations were wrongly taken as 30 and 70 in place of 3 and 27 , respectively, find the correct standard deviation.

  1. A

    10.20

  2. B

    10.24

  3. C

    10.29

  4. D

    10.27

    Fill Out the Form for Expert Academic Guidance!l



    +91



    Live ClassesBooksTest SeriesSelf Learning



    Verify OTP Code (required)

    I agree to the terms and conditions and privacy policy.

    Solution:

      New mean, x¯=100×40+3+273070100=400070100=3930100

                                 =39.3

     Σx2=Nσ2+x¯2 =100(100+1600)=170000 New,  Σx2=170000(30)2(70)2+(3)2+(27)2=1700009004900+9+729=164938 New,  SD= New Σx2N( New x¯)2=164938100(39.3)2=1649.381544.49=104.89=10.24

    Chat on WhatsApp Call Infinity Learn

      Talk to our academic expert!



      +91


      Live ClassesBooksTest SeriesSelf Learning




      Verify OTP Code (required)

      I agree to the terms and conditions and privacy policy.