Question

the sum to be done compulsory on your graph idiotic answers not allowed
The Following Table Shows the marks of the 80 children in an examination
marks : 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80
no. of students : 3 7 15 24 16 8 5 2
draw an ogive for the given distributions in your graph sheet using the scale 2cm=10 units on both axes and estimate
1. the median
2. students who score marks above 65
3.students who dis not pass the exam if passing mark is 32
4.lower and upper quartile


conditions to solve questions
1.do this ques on graph sheet
2.every working must be detailed enough
3. irrelavent or spam or incomplete answers are not accepted and reported immediately
4. best answer=brainliset

Answer 1

The Following Table Shows the marks of the 80 children in an examination

marks : 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80

no. of students : 3 7 15 24 16 8 5 2

draw an ogive for the given distributions in your graph sheet using the scale 2cm=10 units on both axes and estimate

1. the median

2. students who score marks above 65

3.students who dis not pass the exam if passing mark is 32

4.lower and upper quartile

Answer 2

Answer:

The distribution table is in the attachment.

Next attachment gives you the table which will be used to construct the ogive.

Scale to be used: 2cm = 10 units

Thus, 1 cm = 5 units

(1) Median:

Find the point where the less than and more than ogive meet. Draw a perpendicular on the x-axis from the point.

The point found is the median.

Here, the median is 36

(2) 7 Students

(from the more than ogive table)

(3) 25 Students

(from the less than ogive table)

(4) First know the method to find the median with only the less than ogive graph:

1. Find n/2 , where n = total entries on y-axis. Here, it is 80.
2. Next, join the point n/2 with the less than ogive graph through a line parallel to the x-axis. Mark the point where the n/2 point meets the graph line.
3. Draw a perpendicular on the x-axis through the previous point. You get your median.

Now, find the lower quartile:

Here, n = 40 (since 40 is the point where the median was found previously. n/2 = 80/2 = 40. Thus, for lower quartile is 40)

n/2 = 40/2 = 20

Find the point which joins 20 to the lower quartile. Then draw a perpendicular to the x-axis. The point you get on x-axis is 26.5

Find the upper quartile:

Here, n = 40 again (since now we need to treat the latter intervals independently, we will see how many intervals we have in total. We have 80 intervals, among which the latter are the intervals above 40, 80-40 = 40, thus n = 40)

n/2 = 40/2 = 20

But here, we won't take 20. We will instead take 20 units above the point 40 on the y-axis. That point is 40+20 = 60. Thus, 60 is the point from where we need to join the less than graph line.

After you join the line, you get a point. Draw the perpendicular on the x-axis from that point. The point you get is 47

Thus, lower quartile = 26.5

Upper quartile = 47

Do read the whole thing, for better understanding. And feel free to ask the doubts in inbox! :)

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