Question

Find the sum of odd numbers b/w 0 and 50

Answer 1

Answer:

=> 1+3+5+7+...+47+49

a=1 l=49 d=2

=> 49 = 1 + (n-1)2

=> 24 = n-1

=> n = 25

So sum of AP = (a+l)*n/2

=> 50*25/2 = 25*25 = 625

Answer 2

Step-by-step explanation:

The odd numbers between 0 and 50 are 1,3,5,7,9…49

Therefore, it can be observed that these odd numbers are in an A.P.

a=1,d=2,l=49

l=a+(n−1)d

49=1+(n−1)2

48=2(n−1)

n−1=24

n=25

S

n

=

2

n

(a+l)

S

25

=

2

25

(1+49)

=

2

25×50

=625