Q1. The abscissa of the point of intersection of the less than type and of the more than type cumulative frequency curves of a grouped data gives its:
Q2. For the following distribution: Class: 0-5, 5-10, 10-15, 15-20, 20-25 Frequency: 10, 15, 12, 20, 9 The sum of the lower limits of the median class and modal class is:
Q3. If the mode of a distribution is 8 and its mean is 8, then its median is:
Q4. Assertion (A): If the number of observations $n$ is even, then the median is the mean of $(\frac{n}{2})^{th}$ and $(\frac{n}{2}+1)^{th}$ observations. Reason (R): The median divides the data into two equal parts.
Q5. The mean of 20 numbers is 18. If 2 is added to each number, what will be the new mean?
Solve on white paper.
Q6. Find the class mark of the class 10-25 and 35-55.
Q7. In a frequency distribution, if $a = \text{assumed mean} = 55$, $\sum f_i = 100$, $h = 10$ and $\sum f_i u_i = -30$, then find the mean of the distribution.
Q8. The mean of the following data is 53. Find the value of $f_1$ and $f_2$. Class: 0-20, 20-40, 40-60, 60-80, 80-100 Frequency: 15, $f_1$, 21, $f_2$, 17 Total frequency is 100.
Q9. Find the mode of the following distribution: Marks: 0-10, 10-20, 20-30, 30-40, 40-50 No. of Students: 4, 8, 10, 20, 8
Q10. If the median of the distribution given below is 28.5, find the values of $x$ and $y$. Class Interval: 0-10, 10-20, 20-30, 30-40, 40-50, 50-60 Frequency: 5, $x$, 20, 15, $y$, 5 Total frequency is 60.
Q11. Case Study: Electricity Consumption
A survey on the daily electricity consumption (in units) of 50 households in a locality was conducted and the data is recorded as follows:
(i) Find the modal class of the data.
(ii) Calculate the mean daily electricity consumption.
(iii) Calculate the median daily electricity consumption.