Find the upper limit of the first class interval in the class interval: 8-11, 12-15, 16-19...

The following table gives the literacy rate (in percentage) of 35 cities. Find the mean literacy rate by step deviation method.

(A) 66.44
(B) 69.43
(C) 67.39
(D) 71.55

100 surnames were randomly picked up from a local telephone directory and the frequency distribution of the number of letters in the English alphabets in the surnames was obtained as follows: \begin{tabular}{|c|c|c|c|c|c|c|} \hline Number of letters & $1-4$ & $4-7$ & $7-10$ & $10-13$ & $13-16$ & $16-19$ \ \hline Number of surnames & 6 & 30 & 40 & 6 & 4 & 4 \ \hline \end{tabular}

Determine the median number of letters in the surnames. Find the mean number of letters in the surnames. Also, find the modal size of the surnames.

The mode for the following frequency distribution is

\begin{tabular}{lcccc} C.I. & $0-4$ & $4-8$ & $8-12$ & $12-16$ \ Frequency & 4 & 8 & 5 & 6 \end{tabular}

The following table gives the marks obtained by the students of a class in an exam out of 50.

(i) Convert the cumulative frequency distribution into a regular frequency distribution.
(ii) Find the mean.

The following are the marks obtained in Maths by students of Class 8:

$$ \begin{array}{l} 51, 94, 34, 20, 50, 81, 81, 90, 76, 34, 51, 86, 93, 99, 26, 54, 85, 71, 88, 40, 44, 56, 55, 57, \ 78, 53, 81, 78, 65, 78. \end{array} $$

The data have to be grouped to find the mean marks. One of the class intervals made is 60-70.

How many should such class intervals be prepared?

What is the frequency of the last class interval?

What are the upper and lower limits of the first class interval?

What is $\sum \mathrm{f}_{\mathrm{i}}$?

(A) $8, 4, 20, 30, 28$
B $8, 4, 30, 20, 30$
(C) $10, 1, 0, 10, 30$
(D) $10, 4, 10, 0, 30$