IDNStudy.com, ang iyong mapagkukunan para sa mabilis at maaasahang mga sagot. Ang aming mga eksperto ay handang magbigay ng malalim na sagot at praktikal na solusyon sa lahat ng iyong mga tanong.

sum of all the odd numbers from 1 to 101 . how to find?

Sagot :

Answer:

To find the sum of all odd numbers from 1 to 101, you can use the formula for the sum of an arithmetic series. Here's a step-by-step approach:

1. **Identify the Series**: The series of odd numbers from 1 to 101 is: \( 1, 3, 5, \ldots, 101 \).

2. **Find the Number of Terms**: The common difference \( d \) is 2. To find the number of terms (\( n \)), use the formula for the nth term of an arithmetic series:

\[

a_n = a + (n - 1)d

\]

where \( a \) is the first term (1), \( d \) is the common difference (2), and \( a_n \) is the last term (101). Setting up the equation:

\[

101 = 1 + (n - 1) \cdot 2

\]

Solving for \( n \):

\[

101 = 1 + 2n - 2

\]

\[

101 = 2n - 1

\]

\[

102 = 2n

\]

\[

n = 51

\]

3. **Calculate the Sum**: The sum \( S_n \) of an arithmetic series is given by:

\[

S_n = \frac{n}{2} \cdot (a + l)

\]

where \( a \) is the first term, \( l \) is the last term, and \( n \) is the number of terms. Substituting the values:

\[

S_{51} = \frac{51}{2} \cdot (1 + 101)

\]

\[

S_{51} = \frac{51}{2} \cdot 102

\]

\[

S_{51} = 51 \cdot 51

\]

\[

S_{51} = 2601

\]

So, the sum of all odd numbers from 1 to 101 is \( 2601 \).