An examination is taken at three centres each of which has 100 candidates. The mean marks and standard deviation for each centre are given below.
(I^(st)"centre",,45,9.6),(II^(nd)"centre",50,10.8), (III^(rd)"centre",43,9.0):}`
Calculate the standard deviation of all 300 candidates.

An examination is taken at three centres each of the of which has 100 candidates . The mean marks and standard devaition for the each centre are given below : Calculate the mean and standard deviation of all 300 candidates .

Calculate the variance and standard deviation from the data given below: Size of item, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5 Frequency , 3, 7, 22, 60, 85, 32, 8

Calculate the variance and standard deviation from the data given below: Size of item, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5 Frequency , 3, 7, 22, 60, 85, 32, 8

Consider the following statements : (i) Mean of 100 observations is 50 and standard deviation is 10. If 5 is added to each observation the new mean and standard deviation are 55, 10. (ii) Mean of 100 observations is 50 and standard deviation is 10. If each observation is multiplied by 3 then the new mean and standard deviation are 50, 10/3. The true statements are :

The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. One rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases. (i) If wrong item is omitted (ii) If it is replaced by 12.

The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. One rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases. (i) If wrong item is omitted (ii) If it is replaced by 12.

The mean and standard deviation of 20 observations are found to be 10 and 2, respectively. One rechecking, it was found that an observation 8 was incorrect. Calculate the correct mean and standard deviation in each of the following cases. (i) If wrong item is omitted (ii) If it is replaced by 12.

A circular coil of wire consisting of 100 turns each of radius 9 cm carries a current of 0.4 A. The magnitude of the magnetic field at the centre of coil is [ mu_(0) = 1256 xx 10^(-7) Sl unit]

The mean of a finite set S of numbers is 14, the median of this set of numbers is 12, and the standard deviation is 1.8. A new set T is formed by multiplying each member of the set S by 3. Which of the following statements must be true of the set T ? I. The mean of the numbers in set T is 42. II. The median of the numbers in set T is 36. III. The standard deviation of the numbers in set T is 5.4.

A compound formed by elements X and Y has a cubic structure in which X atoms are at the corner of the cube and also at the face centers. Y atoms are present at the body centre and at the edge centre of the cube. a. Celculate (i) Z_(eff') (ii) total number of atoms in the cube, and (iii) formula of the compound. b. If all the atoms are removed from one of the body diagonals of the cube, calculate (i) Z_(eff') (ii) total number of atoms in the cube, and (iii) formula of the compound. c. If all the atoms from the diagonals of the one of the face of the cube are removed, calculate (i) Z_(eff') (ii) total number of atoms in the cube, and (iii) formula of the compound. d. If all the atoms are removed from one of the plane passing through the middle of t he cube, calculate (i) Z_(eff') (ii) total number of atoms in the cube, and (iii) formula of the compound. e. If all the atoms are removed from one of the axes passing through one of the face centres of the cube, calculate (i) Z_(eff') (ii) total number of atoms in the cube, and (iii) formula of the compound.