Question

1 What is the sum of the first 100 natural numbers?​

Answer 1

Answer:

S100=n2[2a+(n−1)d]substituting the values. we getS100=1002[2×1+(100−1)×1]S100=50[2+99]S100=50×101S100=5050∴ The sum of first 100 natural numbers is 5050.

Answer 2

Sum of the 1 to 100 numbers is

n(n+1)/2

100×(100+1)/2

100 ×101/2

50×101

5050