Loading [MathJax]/jax/output/SVG/jax.js
 
+0  
 
0
607
4
avatar

sum of the numbers starting from 14 to 180?

 Nov 22, 2016
 #1
avatar+37165 
0


18014 n   = 16,199

 Nov 22, 2016
 #2
avatar
0

Number of terms=[common difference - first term + last term] / common difference

N =[1-14+180 / 1 = 167 terms

You sum them up as Arithmetic Series: S ={first + last} x number of terms / 2={14+180} x 167/2

=16,199

 Nov 22, 2016
 #3
avatar
0

 

 

I think the 5 year old Gauss did the same problem but added up 1 to 100 in his head with this method. 

 Nov 22, 2016
 #4
avatar+26396 
+5

sum of the numbers starting from 14 to 180?

 

14+15+16++178+179+180=(1413+13)+(1513+13)+(1613+13)++(17813+13)+(17913+13)+(18013+13)=(1+13)+(2+13)+(3+13)++(165+13)+(166+13)+(167+13)=16713+(1+2+3+4++165+166+167)=16713+1+1672167=2171+14028=16199

 

laugh

 Nov 22, 2016

1 Online Users