Question

the mean of weight of 100 persons is 56kg . the mean of weight of males is 58 kg and females is 48 kg then the no. of males is

Answer 1

Answer:  The required number of males is 80.

Step-by-step explanation: Given that the mean of weight of 100 persons is 56 kg, the mean of weight of males is 58 kg and that of females is 48 kg.

We are to find the number of males.

Let n be the number of males. Then, the number of females will be (100 - n).

According to the given information, we have

$100\times56=n\times 58+(100-n)\times48\\\\\Rightarrow 5600=58n+4800-48n\\\\\Rightarrow 5600-4800=10n\\\\\Rightarrow 10n=800\\\\\Rightarrow n=\dfrac{800}{10}\\\\\Rightarrow n=80.$

Thus, the required number of males is 80.

Answer 2

Answer:

.... 80....

Step-by-step explanation:

let there be M males in 100 persons

so,

M × 58 + (100 - M ) ×48 = 56 × 100

10M = 800

M = 80

HENCE,

Number of males is 80

Number of female is 20...

hope it's helpful...