Question

2 + 3 + 4 + …………….. + 100 = __________​

Answer 1

Answer:

Using the concept of AP series

a = 1

d = 1

an = 100

a + (n - 1)×d = 100

2 + (n - 1)×1 = 100

n - 1 = 98

n = 99

Sum = n/2× [a + an]

= 99/2 × (2 + 100)

= 99 × 51

= 5049

Answer 2

Required answer:

5,049

Explanation:

The Numbers are in AP:

Given:

a = 2

d = 1

an = 100

Solution:

an =  a + (n-1) d

100 = 2 + (n -1)1

n = 99

sn= n/2(2a + (n-1)d)

   = 99/2(2(2) + (99-1)1)

   = 5,049