Question

The weight of 9 apples are 50, 60, 65, 62, 67, 70, 64, 45, 48 grams. Their mean weight is
A) 60.5 gram
B) 60 gram
C) 59 gram
D) 62 gram

Answer 1

First find the total weight by adding all the weights of the 9 apples. After that find the mean by substituting the sum of the weight of the apples and total count of numbers by mean formula, $\dfrac{{\sum {{x_i}} }}{n}$. Then divide the numerator by the denominator to get the desired result.

Complete step-by-step answer:
The weight of 9 apples are 50, 60, 65, 62, 67, 70, 64, 45, 48 grams.
We know that the general formula to find the mean value is,
Mean $= \dfrac{{\sum {{x_i}} }}{n}$
The sum of the 9 apples are,
$\Rightarrow \sum {{x_i}} = 50 + 60 + 65 + 62 + 67 + 70 + 64 + 45 + 48$
Add the values on the right side,
$\Rightarrow \sum {{x_i}} = 531$
Now, substitute the value in the mean formula,
$\Rightarrow$ Mean $= \dfrac{{531}}{9}$
Divide the numerator by the denominator,
$\therefore x = 59$

Hence, option (C) is correct.

Note: Arithmetic mean represents a number that is obtained by dividing the sum of the elements of a set by the number of values in the set. So, you can use the layman term Average, or be a little fancier and use the word “Arithmetic mean“. Arithmetic means utilizing two basic mathematical operations, addition and division to find a central value for a set of values.