Question

The average of 50 numbers is 38. If two numbers namely, 45 and 55 are discarded, the average of remaining numbers is:
1) 37
2) 36.5
3) 37.52
4) 37.5

Answer 1

37.5.
Avg for 50 numbers is 38. the total is 38x50= 1900
the total of discarded numbers is 45+55=100. hence the total for 48 numbers is 1900-100=1800.
the new average is 1800 / 48= 37.5

Answer 2

Answer:

The average of the remaining numbers will be 37.5.

Solution:

The average of 50 numbers is 38  

We know that,

$\text { Average } = \frac { \text { Sum of the observations } } { \text { Total number of Observations} }$

Here, total = 50 and average = 38

The sum of all the 50 numbers are = 50×38 = 1900

The Sum of the given two numbers = 45+55 = 100

After discarding two numbers, total numbers left now are = 48

The total sum of the remaining 48 numbers are = 1900-100 = 1800

∴  The remaining average of the 48 numbers are

$= \frac {1800}{48} = 37.5$

Thus, the average of the remaining numbers will be 37.5.