Free account: track your progress — Sign up free

Post-UTME Mathematics 2013 Objective — Question 39

Question 39 of 100 from the Post-UTME Screening (Post-UTME) Mathematics 2013 Objective paper, with the correct answer and a full explanation.

Advertisement

Find the standard deviation of the data using the table above (classes 1-3, 4-6, 7-9 with frequencies 5, 8, 5)

  • A. 5
  • B. 6
  • C. 5/3
  • D. √5Correct

Explanation

Using midpoints 2,5,8: mean=5, and Σf(x-mean)²/n = 90/18 = 5, so standard deviation = √5.

Advertisement

Sign up free to unlock

  • Score tracking
  • Practice history
  • Saved questions
  • Progress dashboard
  • Personalized sessions
  • Weak-topic breakdown

…and/or go further with premium services and No Ads.