For a certain, frequency table which has been partly reproduced here, the Arithmetric mean was found to be Rs 28.07 [table] Income (in Rs) | No. of workers ; 15 20 25 30 35 40 | 8 12 ? 16 ? 10 [/table] If the total number of workers is 75, then missing frequencies are respectively

Question

Dr. Abubacker · Accepted Answer

(b)
$\because\ \ 8 + 12 + f_{1} + 16 + f_{2} + 10 = 75$
$\Rightarrow \ \ \ f_{1} + f_{2} = 29$ ...(i)
And $120 + 240 + 25f_{1} + 480 + 35f_{2} + 400 = 28.07 	imes 75$
$\Rightarrow \ \ \ 1240 + 25f_{1} + 35f_{2} = 2105.25$
$\Rightarrow \ \ \ 5f_{1} + 7f_{2} = 173.25$ ...(ii)
On solving eqs. (i) and (ii), we get
$f_{1} = 15$ and $f_{2} = 14$

Q. For a certain, frequency table which has been partly reproduced here, the Arithmetric mean was found to be Rs 28.07 [table] Income (in Rs) | No. of workers ; 15 20 25 30 35 40 | 8 12 ? 16 ? 10 [/table] If the total number of workers is 75, then missing frequencies are respectively

Explanation

Reviewed by Dr. Abubacker

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