The mean and standard deviation of 100 observations were calculated as 40 and 5.1 respectively by a student who took by mistake 50 instead of 40 for one observation. What are the correct mean and standard deviation?

A standard obtained the mean and standard deviation of 100 observations as 40 and 5.1 respectively. Later it was discovered that he had wrongly copied down and observation as 50 instead of 40. Calculate the true mean and standard deviation.

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.

The mean and standard deviation of 18 observations are found to be 7 and 4 respectively. On rechecking it was found that an observation 12 was misread as 21. Calculate the correct mean and standard deviation.

The mean and standard deviation of a binomial variate X are 4 and sqrt(3) respectively. Then , P(Xge1)=

If the men and standards deviation of 100 observations are 50 and 4 respectively. Find the sum of all the observations and the sum of their squares.

Mean and standard deviations of 10 observations are 20 and 2 respectively. If p (p ne 0) is multiplied to each observation and then q (q ne 0) is subtracted then new mean and standard deviation becomes half of original value . Then find q

Mean and standard deviation of 100 observations of are found to be 40 and 10. If at the time of calculation two observations are wrongly taken as 30 and 70 instead of 3 and 27 respectively. Find the correct standard deviation.

The mean and standard deviation of a group of 100 observations were found to be 20 and 3 respectively. Later on it was found that three observations were incorrect , which were recorded as 21, 21 and 18 . Find the mean and standard deviation if the incorrect observations are omitted.