Doubts
Sign in
12thPass logo
New chatPYQ LibraryDoubtsRank report
Sign in to see Recents
Sign in to save progress →
Doubts
Sign in

Statistics question

2023 · 10 Apr · Shift 1 · Q42
Guest · try one question or challengeGuest · try one question or challenge
  1. PYQ Library
  2. /JEE Main
  3. /Mathematics
  4. /Statistics
  5. /2023 · 10 Apr · Shift 1 · Q42

Statistics question

2023 · 10 Apr · Shift 1 · Q42

JEE MainMathematicsStatisticsNumerical+4 / −1

If the mean of the frequency distribution

Class : 0-10 10-20 20-30 30-40 40-50
Frequency : 2 3 xxx 5 4

is 28, then its variance is ‾\underline{\hspace{2cm}}​.

Numerical answer
PreviousNext

More from Statistics

  • Let μ be the mean and σ be the standard deviation of the distribution where ∑fi​=62. If [x] denotes the greatest integer ≤x, then [μ2+σ2] is equal to : Includes table2023 · MCQ
  • Let sets A and B have 5 elements each. Let the mean of the elements in sets A and B be 5 and 8 respectively and the variance of the elements in sets A and B be 12 and 20 respectively. A new set C of 10 elements is formed by subtracting 3…2023 · MCQ
  • Let the mean of 6 observations 1,2,4,5,x and y be 5 and their variance be 10 . Then their mean deviation about the mean is equal to :2023 · MCQ
  • Let the positive numbers a1​,a2​,a3​,a4​ and a5​ be in a G.P. Let their mean and variance be 1031​ and nm​ respectively, where m and n are co-prime. If the mean of their reciprocals is 4031​…2023 · Numerical
  • Let the mean of the data be 5. If m and σ2 are respectively the mean deviation about the mean and the variance of the data, then m+σ23α​ is equal to ​ Includes table2023 · Numerical
  • The mean and standard deviation of the marks of 10 students were found to be 50 and 12 respectively. Later, it was observed that two marks 20 and 25 were wrongly read as 45 and 50 respectively. Then the correct variance is ​…2023 · Numerical
  • The mean and standard deviation of 10 observations are 20 and 8 respectively. Later on, it was observed that one observation was recorded as 50 instead of 40. Then the correct variance is :2023 · MCQ
  • Let the six numbers a1​,a2​,a3​,a4​,a5​,a6​, be in A.P. and a1​+a3​=10. If the mean of these six numbers is 219​ and their variance is σ2, then 8 σ2 is equal to :2023 · MCQ