SOLUTION: If 1+2+3+...+50=1275, then 51+52+53+...+100=? A. 1325 B. 2325 C. 3775 D. 63750

Algebra ->  Subset -> SOLUTION: If 1+2+3+...+50=1275, then 51+52+53+...+100=? A. 1325 B. 2325 C. 3775 D. 63750      Log On


   

Question 995055: If 1+2+3+...+50=1275, then 51+52+53+...+100=?
A. 1325
B. 2325
C. 3775
D. 63750
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
1%2B2%2B3+...+50=1275, we can find the sum of these 50 numbers if we multiply half of the sum of first and last number by 50 like this:

%28%281%2B50%29%2F2%29%2A50=%2851%2F2%29%2A50=25.5%2A50=1275
then 51%2B52%2B53+...+100= will be
%28%2851%2B100%29%2F2%29%2A50=%28151%2F2%2950=75.5%2A50=3775
so, answer is: C. 3775