The below workout with step by step calculation shows how to find what is the average of numbers from 200 to 800 manually.
step 1 Address the formula and input values.
Formula: Average = Total Sum of Numbers / Total Count of Numbers
Input values:
The numbers from 200 to 800 are
200, 201, 202, 203, . . . . , 798, 799, 800
Total Count of Numbers = 601
step 2 Find the sum of numbers from 200 to 800.
sum = 200 + 201 + 202 + . . . . + 799 + 800
= 300500
step 3 Divide the sum by 601
Average = 300500/601
= 500
500 is an average of numbers from 200 to 800.