Question

is 55 kg, find the weight
24. The mean score of 25 observations is 80 and the mean score of another
55 observations is 60. Determine the mean score of the whole set of
observations.
12 morke in English, 44 marks in Hindi, 75 marks in​

Answer 1

$\large\mathfrak \pink{Solution:-}$

$\underline \mathbb{GIVEN:-}$

Mean of 25 observations is 80 .

Mean of another 55 observations is 60.

$\underline \mathbb{TO  \: FIND:-}$

The mean score of the whole set of observations.

$\underline \mathbb{BY  \: THE  \: PROBLEM:-}$

Mean of 25 observations is 80 .

Total value of 25 observations is 25  × 80 = 2000

Mean of another 55 observations is 60.

Total value of 55 observations is 55  × 60 = 3300

So, Total observations = 25 + 55 = 80 is 2000 + 3300 = 5300

 $Mean =\frac{ Total\: observations}{Total\: value\: of\: observations }\\ \\ \implies Mean = \frac{5300}{8} \\ \\ \implies Mean =66.25$

$\underline \mathbb{ANSWER:-}$

The mean score of the whole set of observations is 66.25