The marks of 11 students out of 25 marks are as follows 21,20,13,15,10,20,15,21,20,18 and 14 Find the mean median and range
Answers
Answer:
Mean=17
Median=18
Mode =20
Step-by-step explanation:
Given:-
The marks of 11 students out of 25 marks are as follows 21,20,13,15,10,20,15,21,20,18 and 14
To find:-
Find the mean median and range .
Solution:-
1)Mean of the data:-
Given observations=21,20,13,15,10,20,15,21,20,18 and 14
Sum of all observations=21+20+13+15+10+20+15+21+20+18+14=187
Number of all observations=11
Mean= Sum of all observations/Number of all observations
=>Mean=187/11
Mean=17
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2)Median of the data:-
Given observations=21,20,13,15,10,20,15,21,20,18 and 14
On writting them into ascending order
10,13,14,15,15,18,20,20,20,21,21
Number of observations=(n)=11 is an odd number
So median =(n+1)/2 th observation
=>Median=(11+1)/2 th observation
=>Median=12/2 th observation
=>Median=6 th observation
In the given data 6th observation=18
Median=18
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3)Mode of the given data:-
Given observations=21,20,13,15,10,20,15,21,20,18 and 14
Given observations=21,20,13,15,10,20,15,21,20,18 and 14On writting them into ascending order
Given observations=21,20,13,15,10,20,15,21,20,18 and 14On writting them into ascending order10,13,14,15,15,18,20,20,20,21,21
Most occuring data is the mode
Here, most occuring observation=20
20 occurs 3 times
Mode =20
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Step-by-step explanation:
Range =highest value - lowest value
22-10 = 11
mean = sum of observation/Total number of observation
=21+20+13+15+10+20+15+21+20+18+14/11
= 187/11
=17
median =10,13,14,15,15,18,20,20,20,21,21
=18
mode =20