Find The Sum 1 + 2 + 3 + 4 + 5 + …………………. + 100

Answer: 1 + 2 + 3 + 4 + 5 + …………………. + 100 is an AP (Arithmetic Progression) series and the formula for computing the sum of such sequential series has been stated below:-

S=n / 2[2a+(n-1)*d]

Where ”S” is the sum of the AP series,

“a” is the first term,

“d” is the common difference between the consecutive terms, and

“n” is the number of terms in the AP series.

Here, a = 1; d = 1;and n = 100

Now, put the values in the formula

S=100 / 2 [2(1)+(100-1)*1]

S=100 / 2(2+99)

S=50 (101)=5050

Therefore, the sum of 1+2+3+4……100 is 5050.