For two data sets, each of size 5, the variances are given to be 4 and 5 and the corresponding means are given to be 2 and 4, respectively. The variance of the combined data set is
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The following table gives the distribution of the life time of 400 neon lamps:
Find the mean deviation from the median for the following data:
Size:, 10, 11, 12, 14, 15
Frequency:, 2, 3, 8, 3, 4
The following are some particulars of the distribution of weights of boys and girls in a class:
Which of the distributions is more variable?
While calculating eh mean and variance of 10 readings, a student wrongly used the reading of 52 for the correct reading 25. He obtained the mean and variance as 45 and 16 respectively. Find the correct mean and the variance.
The distribution below gives the weights of 30 students of a class. Find the median weight of the students.
Find the mean and standard deviation using short-cut method
Draw a 'more than' given for the data given below which gives the marks of 100 students.
If the mean of 25 observations is 27 and each observation is decreased by 7, what will be the new mean ?