Question 1
Find the mean marks of students for the following distribution
$\begin{matrix} M a r k s & N u m b e r o f s t u d e n t s 0 a n d a b o v e & 80 10 a n d a b o v e & 77 20 a n d a b o v e & 72 30 a n d a b o v e & 65 40 a n d a b o v e & 55 50 a n d a b o v e & 43 60 a n d a b o v e & 28 70 a n d a b o v e & 16 80 a n d a b o v e & 10 90 a n d a b o v e & 8 100 a n d a b o v e & 0 \end{matrix}$

Open in App

Solution

$\begin{matrix} M a r k s & C l a s s m a r k s & N u m b e r o f s t u d e n t s & f_{i} & f_{i} x_{i} 0 - 10 & 5 & 80 & 3 & 15 10 - 20 & 15 & 77 & 5 & 75 20 - 30 & 25 & 72 & 7 & 175 30 - 40 & 35 & 65 & 10 & 350 40 - 50 & 45 & 55 & 12 & 540 50 - 60 & 55 & 43 & 15 & 825 60 - 70 & 65 & 28 & 12 & 780 70 - 80 & 75 & 16 & 6 & 450 80 - 90 & 85 & 10 & 2 & 170 90 - 100 & 95 & 8 & 8 & 760 100 - 100 & 105 & 0 & 0 & 0 \sum f_{i} x_{i} = 4140 \end{matrix}$
$∴ M e a n = \frac{\sum f_{i} x_{i}}{N} = \frac{4140}{80} = 51.75$

Suggest Corrections

Similar questions

\begin{matrix} M a r k s & N u m b e r o f s t u d e n t s B e l o w 10 & 5 B e l o w 20 & 9 B e l o w 30 & 17 B e l o w 40 & 29 B e l o w 50 & 45 B e l o w 60 & 60 B e l o w 70 & 70 B e l o w 80 & 78 B e l o w 90 & 83 B e l o w 100 & 85 \end{matrix}

\begin{matrix} M a r k s & N u m b e r o f s t u d e n t s 0 a n d a b o v e & 80 10 a n d a b o v e & 77 20 a n d a b o v e & 72 30 a n d a b o v e & 65 40 a n d a b o v e & 55 50 a n d a b o v e & 43 60 a n d a b o v e & 28 70 a n d a b o v e & 16 80 a n d a b o v e & 10 90 a n d a b o v e & 8 100 a n d a b o v e & 0 \end{matrix}

\begin{matrix} No. of students & 8 & 12 & 20 & 10 & 6 & 4 Marks & 20 & 30 & 40 & 50 & 60 & 70 \end{matrix}

Join BYJU'S Learning Program