Embibe Experts Solutions for Exercise 1: Assignment

The mean and standard deviation of marks obtained by $100$ students in a class in given subject are as follows:

Which of these subjects, show the highest variability in marks and which shows the lowest?

The mean life of a sample of $100$ bulbs was $1850$ hours and the standard deviation was $6$ hours. A second sample of $80$ bulbs has a mean life of $1980$ hours and standard deviation of $8$ hours. Find the overall standard deviation.

Two sets of $20$ observation, have same standard deviation $10$. The first set has mean $21$ and second has mean $24$. Determine the standard deviation of the set obtained by combining the given two sets.

Mean and standard deviation of $100$ observations were found to be $50$ and $20$ respectively. If at the time of calculation two observations were wrongly taken as $196$ and $144$ instead of $96$ and $54$ respectively. Find the correct standard deviation.

While calculating the mean and standard deviation of $20$ readings, a student wrongly used the reading $72$ for the correct reading $27$. He obtained the mean and standard deviation as $50$ and $18$ respectively. Find the correct mean and standard deviation.

The mean and standard deviation of $40$ observations are found to be $20$ and $8$ respectively. On rechecking it was found that an observation $36$ was incorrect. Calculate the correct mean and standard deviation if that observation is omitted.

Find the mean deviation about the median for the following data:

From the marks scored by Ajay and Akshay in $10$ tests, find out whose performance is more consistent.