Question

The following table gives the height of trees

Height	Less than $7$	Less than $14$	Less than $21$	Less than $28$	Less than $35$	Less than $42$	Less than $49$	Less than $56$
No. of trees	$25$	$45$	$95$	$140$	$235$	$275$	$320$	$360$

Draw "less than" ogive and "more than" ogive

Answer 1

Consider the following table.

Height (less than)	Height-class	No. of trees	Cumulative frequency	Suitable points
7	0-7	26	26	(7,26)
14	7-14	31	57	(14,57)
21	14-21	35	92	(21,92)
28	21-28	42	134	(28,134)
35	28-35	82	216	(35,216)
42	35-42	71	287	(42,287)
49	42-49	54	341	(49,314)
56	49-56	19	360	(56,360)

Now draw the less than ogive using suitable points.

Now prepare the table for cumulative frequency table for more than series

Height (more than)	Height-class	No. of trees	Cumulative frequency	Suitable points
0	0-7	26	360	(0,360)
7	7-14	31	334	(7,334)
14	14-21	35	303	(14,303)
21	21-28	42	268	(21,268)
28	28-35	82	226	(28,226)
35	35-42	71	144	(35,144)
42	42-49	54	73	(42,73)
49	49-56	19	54	(49,54)

Now draw the more than ogive using suitable points.