# Applied Mathematics for Electrical Engineering(3130908)

BE | Semester 3  Unit : Basic Statistics

## Q5 (a) Winter-2019   Define mean, median and mode for the ungrouped data.

Unit : Basic Statistics

## Q5 (b) Winter-2019   Find the first four moments about mean

Unit : Basic Statistics

## Q5 (c ( i )) Winter-2019   Attempt the following. In a distribution of two different groups the variances are 15 and 27. Whereas the third central moments are 32.4 and 67.56 respectively. Compare the skewness of two groups.

Unit : Basic Statistics

## Q5 (c ( ii )) Winter-2019   Two automatic filling machines A and B are used to fill mixture of cement, concrete and beam. A random sample of beam on each machine showed following results. $\mathrm{A}$ $\mathrm{32}$ $\mathrm{28}$ $\mathrm{47}$ $\mathrm{63}$ $\mathrm{71}$ $\mathrm{39}$ $\mathrm{10}$ $\mathrm{60}$ $\mathrm{96}$ $\mathrm{14}$ $\mathrm{B}$ $\mathrm{19}$ $\mathrm{31}$ $\mathrm{48}$ $\mathrm{53}$ $\mathrm{67}$ $\mathrm{90}$ $\mathrm{10}$ $\mathrm{62}$ $\mathrm{40}$ $\mathrm{80}$ Find standard deviation of each machine and also comment on the performance of the two machine.

Unit : Basic Statistics

## Q5 (a) Winter-2019   The pH solution is measured eight times using the same instrument and data obtained are as follows: Calculate the mean, variance and standard deviation.

Unit : Basic Statistics

## Q5 (b) Winter-2019   In environmental geology computer simulation was employed to estimate how far a block from a collapsing rock wall bounce down a soil slope. Based on the depth, location and angle of block soil impact marks left on the slope of the actual rock fall, the following 10 rebounds lengths (meters) were estimated. Compute mean and standard deviation of the rebounds.

Unit : Basic Statistics

## Q5 (c ( i )) Winter-2019   Attempt the following. Find the coefficient of quartile deviation for the following data: .

Unit : Basic Statistics

## Q5 (c ( ii )) Winter-2019   State the formula for coefficient of skewness based on central moments and find it for the following frequency distribution. Class 50 - 55 55 - 60 60 - 65 65 - 70 70 - 75 y 8 10 15 17 8

Unit : Basic Statistics