The mean of marks obtained by 100 students was found to be 40.Later on it was discovered that a score of 53 was misread as 83.Find the correct mean.
mj7172:
100*40=4000 - 83+53=3970/100=39.70
No no non no
Answers
Answered by
15
Hey there!
Mean of 100 students marks = 40 .
Sum of 100 students marks = 4000
Now, Difference between correct one and misread one = -30 .
Now, Actual sum = 4000- 30 = 3970 .
Correct mean = 3970/100 = 39.7
Mean of 100 students marks = 40 .
Sum of 100 students marks = 4000
Now, Difference between correct one and misread one = -30 .
Now, Actual sum = 4000- 30 = 3970 .
Correct mean = 3970/100 = 39.7
Answered by
5
sum of marks obtained by students / no. of students
= mean
so , given incorrect mean = 40
no. of students = 100
incorrect sum of marks obtained by students = 40*100 = 4000
since one reading 53 misread as 83 so ,
correct sum = 4000-83+53= 3970
so correct mean = correct sum / no. of students
= 3970/100 = 39.7
= mean
so , given incorrect mean = 40
no. of students = 100
incorrect sum of marks obtained by students = 40*100 = 4000
since one reading 53 misread as 83 so ,
correct sum = 4000-83+53= 3970
so correct mean = correct sum / no. of students
= 3970/100 = 39.7
i think the correct sun is this 4000-(83+53) bcoz without bracket your answer is wrong...
no bro its correct
cos its 4000-(83-53)
not 4000-(83+53)
oh
I'm really sorry
i misunderstand
And bye the way I'm not your bro..I'm a girl
okk
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