Q9 of 40 Page 935

Using short cut method, find the mean, variation and standard deviation for the data :

Here, we apply the step deviation method with A = 50 and h = 10

To find: MEAN



Now,






To find: VARIANCE







= 130.67


To find: STANDARD DEVIATION




= 11.43


More from this chapter

All 40 →
7

Using short cut method, find the mean, variation and standard deviation for the data :

 8

Using short cut method, find the mean, variation and standard deviation for the data :























Class



30-40



40-50



50-60



60-70



70-80



80-90



90-100



Frequency



3



7



12



15



8



3



2



 1

If the standard deviation of the numbers 2, 3, 2x, 11 is 3.5, calculate the possible values of x.

 2

The variance of 15 observations is 6. If each observation is increased by 8, find the variance of the resulting observations.