Mathematics
Study the graph and answer the questions that follow :
(a) Make a frequency table for the information provided in the graph.
(b) The number of students whose height is less than 150 cm.
(c) The total number of students.
(d) The modal height.
(e) The difference in the modal height and the mean height, if the average height of the students is 145.5 cm.
Answer
(a)
| Class | Frequency (f) | Cumulative frequency (c.f.) |
|---|---|---|
| 120-130 | 6 | 6 |
| 130-140 | 29 | 35 |
| 140-150 | 34 | 69 |
| 150-160 | 22 | 91 |
| 160-170 | 12 | 103 |
(b) From the above table,
The number of students whose height is less than 150 cm = 69.
(c) From the above table,
The total number of students = 103.
(d) From graph,
The modal height = 143 cm.
(e) Mean height = Average height = 145.5
Difference in the modal height and the mean height :
145.5 - 143 = 2.5 cm
Hence, difference between modal height and the mean height = 2.5 cm
Related Questions
Plot the points A(2, 2) and B(6, -2) in the graph and answer the following :
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(b) Reflect points A in line y = -2 to point C and write the co-ordinates of point C.
(c) Find a point P on CD which is invariant under reflection in x = 0, write its co-ordinates.
(d) Write the geometrical name of the closed figure ABCD.
(e) Write the co-ordinates of the point of intersection of the diagonals of ABCD.
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(b) Reflect B on y-axis to B’.
(c) Reflect C on x-axis to C’.
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(e) Join the points A, B, C, D, C’, B, A’, B’ and A to form a closed figure. Name the closed figure BCDC’.
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(a) Represent the above distribution by an ogive.
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