Question

The following are the marks of the 30 students in statistics. prepare a frequency distribution taking the class−intervals as 10−20, 20−30 and so on.

12	33	23	25	18	35	37	49	54	51	37	15	33	42	45
47	55	69	65	63	46	29	18	37	46	59	29	35	45	27

Answer 1

In the form of frequency distribution, the given data can be arranged as follows.

Marks	Tally Marks	Number of students (Frequency)
10 - 20 20 - 30 30 - 40 40 - 50 50 - 60 60 - 70	$\mathrm{{\rm I}{\rm I}{\rm I}{\rm I}}$ $\bcancel{\mathrm{{\rm I}{\rm I}{\rm I}{\rm I}}}$ $\bcancel{\mathrm{{\rm I}{\rm I}{\rm I}{\rm I}}}\mathrm{{\rm I}{\rm I}}$ $\bcancel{\mathrm{{\rm I}{\rm I}{\rm I}{\rm I}}}\mathrm{{\rm I}{\rm I}}$ $\mathrm{{\rm I}{\rm I}{\rm I}{\rm I}}$ $\mathrm{{\rm I}{\rm I}{\rm I}}$	4 5 7 7 4 3
		$\sum _{}f=30$