R K Bansal Solutions for Exercise 1: EXERCISE

Find the mean of the following data: $30,32,24,34,26,28,30,35,33,25$ and show that the sum of the deviations of all the given observation from the mean is zero.

Find the median of the following data: $30,32,24,34,26,28,30,35,33,25$.

Find the mean and median of the data: $35,48,92,76,64,52,51,63 \mathrm{and} 71$. If $51$ is replaced by $66$, what will be the new median?

If the mean of observations $x, x+2, x+4, x+6$ and $x+8$ is $11$, find the mean of first three observations.

Find the mean and median of all the positive factors of $72$.

The mean weight of $60$ students in a class is $40 \mathrm{kg}$. The mean weight of boys is $50 \mathrm{kg}$ while that of girls is $30 \mathrm{kg}$. Find the number of boys and girls in the class.

The average of $n$ numbers $x_1,x_2,x_3\dots ..x_n$ is $A$. If $x_1$ is replaced by $(x+a)x_1,x_2$ is replaced by $(x+a)x_2$ and so on. Find the new average.

The heights (in $\mathrm{cm}$ ) of the volley- ball players from team $A$ and team $B$ were recorded as: Team $A: 180, 178, 176, 181, 190, 175, 187$ Team $B: 174, 175, 190, 179, 178, 185, 177$ Which team had the greater average height? Find the median of team $A$ and team $B$.