Adding Consecutively

Algebra Level 2

1+2+3+4+5+6....1,000,000 =?


The answer is 500000500000.

Martin Minikes by Martin Minikes , 16, USA

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

2 solutions

Jordan Cahn
Nov 9, 2018

1 + 2 + ⋯ + n = n ( n + 1 ) 2 1 + 2 + ⋯ + 1 , 000 , 000 = 1 , 000 , 000 × 1 , 000 , 001 2 = 500 , 000 × 1 , 000 , 001 = 500 , 000 , 500 , 000 \begin{aligned} 1+2+\cdots + n &= \frac{n(n+1)}{2} \\ 1+2+\cdots+1{,}000{,}000 &= \frac{1{,}000{,}000\times1{,}000{,}001}{2} \\ &=500{,}000\times1{,}000{,}001 \\ &=\boxed{500{,}000{,}500{,}000} \end{aligned}

3 Helpful 1 Interesting 0 Brilliant 1 Confused
Martin Minikes
Nov 13, 2018

YOU NEED TO PAIR THE 1ST AND LAST NUMBERS TO MAKE 1,000,001 AND THERE ARE 500,000 PAIRS ,SO 1,000,001 TIMES 500,000= 500,000,500,000

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...