Question 803686
1,3,5,7,

this is an AP

a=1
d=2
n=50

Sn sum of n terms ={{{ (n/2)(2a+(n-1)d)}}}

plug the values

Sn ={{{( 50/2)( 2*1+(50-1)*2)}}}

=25(2+98)
=25*100
2500