Question

what is 1+2+3+4+5 all the way plus 99+100?

I'm in 3rd grade advanced math and I need help!

Answer 1

You can use Gauss method...

Sum from 1 to n = [n(n+1)] / 2

So... 1 to 100 = [100(100+1)] / 2

= [100(101)] / 2
= [10100] / 2
= 5050

Answer 2

`1+2+3+4+\ldots+99+100=\\ (1+100)+(2+99)+(3+98)+\ldots(50+51)=\\ 50\cdot101=\\ 5050`