FINDING THE SUM OF ALL EVEN NUMBERS STARTING FROM 2

 

4)

FINDING THE SUM OF ALL EVEN NUMBERS STARTING FROM 2

RULE:

 ( MULTIPLY THE AMOUNT OF NUMBERS IN THE GROUP BY ONE MORE THAN THEIR NUMBER )

We shall use this rule to find the sum of all even numbers from 1 to 100. Hall of the numbers will be even and half will be odd, which means there are 50 even numbers  from 1 to 100.

Applying the rule,

50x 51 = 2,550

Thus the sum of all even numbers from 1 to 100 is 2,550.In Short Cut 2 the sum of all the numbers from 1 to 99 is found to be 4,950 : consequently the sum of all numbers from 1 to 100 is 5,050.In Short Cut 3 the sum of all odd numbers from 1 to 100 is found to be 2,500.Our answer for the sum of all the even numbers  from 1 to 100 is therefore in agreement

Sum of all numbers 5,050 – Sum of all odd numbers 2,500 = Sum of all even numbers 2,550