Question

Find the sum of the odd number between 0 and 50

Answer 1

1+3+5+7+......+49

=25×(1+49)/2 (sum of A.P.)

=25×25

=625(ans)

Hope this helps you mate....

If yes please mark me as brainliest.....

Answer 2

$\bf \: Question$

Find the sum of the odd numbers between 0 and 50.

$\bf \: Solution$

The odd numbers between 0 and 50 are 1, 3,

5,....., 49 which form an AP.

$\bf \: Here ,\: first \: term \: (a) = 1, \: last \: term \: (l) = 49$

$\bf \: and \: common \: difference \: (d) = 3 - 1 = 2.$

Let there are n numbers in the AP.

$\bf \: Then, \: nth \: term \: (a_n) = a + (n - 1) \: d = l$

$\implies \: \: \: \: \: \: \: \: \: \: \: \bf \: 1 + (n - 1) \: (2) = 49$

$\implies \: \: \: \: \: \: \: \: \: \: \: \: \: \ \: \bf \: 2 \: (n - 1) = 48$

$\implies \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \bf \: n - 1 = 24 \implies \: n = 25$

$\bf \: Now, \: sum \: of \: n \: terms \: S_n \: = \: \frac{n}{2} \: (a + l)$

$\therefore \: \: \: \: \bf \: Sum \: of \: 25 \: terms, \: S_2_5 \: = \: \frac{25}{2} \: (1 + 49) = \: \frac{25}{2} \times 50$

$\: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \bf \: = \: 25 \times 25 \: = \: \boxed{\red{625}}$