Question

S=1+2+3+........+100

Answer 1

Answer:

5050

Step-by-step explanation:

Gauss has derived a formula to solve addition of arithmatic series to find the sum of the numbers from 1 to 100 as follows:

1 + 2 + 3 + 4 + … + 98 + 99 + 100

First he has splitted the numbers into two groups (1 to 50 and 51 to 100), then add these together vertically to get a sum of 101.

1 + 2 + 3 + 4 + 5 + … + 48 + 49 + 50

100 + 99 + 98 + 97 + 96 + … + 53 + 52 + 51

1 + 100 = 101

2 + 99 = 101

3 + 98 = 101

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48 + 53 = 101

49 + 52 = 101

50 + 51 = 101

It was realized by him that final total will be fifty times of 101 means:

50(101) = 5050.

Based on this, Gauss has derived formula as:

The sequence of numbers (1, 2, 3, … , 100) is arithmetic and we are looking for the sum of this series of sequence. As per Gauss, the special formula derived by him can be used to find the sum of this series:

S is the sum of the series and n is the number of terms in the series, in present case, from 1 to 100, Hence

As per the Gauss formula, the sum of numbers from 1 to 100 will be 5050.

Answer : 5050