Question

A student wanted to find the sum of all the even numbers from 1 to 100. He said:

Answer 1

Answer:

The statements are incorrect as: The sum of even numbers from 1 to 100(i.e. 2550) is not double\twice of the sum of odd numbers from 1 to 100(i.e. 2500).

Step-by-step explanation:

We know that sum of an Arithmetic Progression(A.P.) is given by:

where 'n' denotes the "number" of digits whose sum is to be determined, 'a' denotes the first digit of the series and '' denote last digit of the series.

Now the sum of even numbers i.e. 2+4+6+8+....+100 is given by the use of sum of the arithmetic progression since the series is an A.P. with a common difference of 2.

image with explanation

Hence, sum of even numbers from 1 to 100 is 2550.

Also the series of odd numbers is an A.P. with a common difference of 2.

sum of odd numbers from 1 to 100 is given by: 1+3+5+....+99

.

Hence, the sum of all the odd numbers from 1 to 100 is 2500.

Clearly the sum of even numbers from 1 to 100(i.e. 2550) is not double of the sum of odd numbers from 1 to 100(i.e. 2500).

Hence the statement is incorrect.

Step-by-step explanation: