Question

find the sum of 100 terms of the A.P 0.7, 0.71 0.72, ..........

Answer 1

Solution is in the attachment

Answer 2

Answer:

119.5

Step-by-step explanation:

Given series is 0.7, 0.71, 0.72.

Clearly, this series is in AP with:

First term a = 0.7

Common difference(d) = 0.71 - 0.7

                                      = 0.01

Now,

We know that Sum of n terms sn = (n/2)[2a + (n - 1) * d]

Here, we have to find sum of 100 terms.So,

S₁₀₀ = (n/2)[2(0.7) + (100 - 1) * 0.01]

      = (100/2)[1.4 + 99 * 0.01]

      = (100/2)[2.39]

      = 50 * 2.39

      = 119.5.

Hope it helps!