Nepal Rastra Bank - Math Previous Exam Question with Answer - Arithmetic Mean Question

Introduction - Arithmetical Mean

In science and insights, the math mean, or just the mean or normal when the setting is clear, is the whole of a gathering of numbers isolated by the quantity of numbers in the accumulation. The number-crunching mean is a numerical portrayal of the common estimation of a progression of numbers, registered as the whole of the considerable number of numbers in the arrangement partitioned by the include of all numbers the arrangement. The number juggling mean is in some cases alluded to as the normal or essentially as the mean. 

The math mean, likewise called the normal or normal esteem, is the amount acquired by summing at least two numbers or factors and afterward partitioning by the quantity of numbers or factors. The number-crunching mean is essential in statistics.The math mean of an arrangement of information is found by taking the aggregate of the information, and after that partitioning the total by the aggregate number of qualities in the set. A mean is generally alluded to as a normal.

Solution in English

Here,

Total year (ΣX) and the total student number (N)
8 years of age 13 = 8 * 13 = 104

3 years of age = 3 * 16 = 48
9 years of age 14 = 9 * 14 = 126
4 years of age 18 = 4 * 18 = 72


Now, Mean = ΣX / N
(ΣX) = 104 + 126 + 48 + 72 = 350
N = 8 + 9 + 3 + 4 = 24

= 350/24
= 14.58


Therefore, Mean = 14.58.