The sum of the numbers given is 31. 1 + 2 + 4 + 8 + ... + 2n = 2n+1 - 1
26
Sum = 79*(79+1)/2 = 79*80/2 = 3160
25
The mater is that if you do 1+1=2 then just add the sum with its self, so you have 2+2=4 and 4 is the answer
4 1/2
The sum of 3x plus 2 and -4 plus 3 is 3x+1 if the equation is (3x+2)+(-4+3). If they are two separate questions, 3x+2 remains as itself while -4+3=-1.
The answer is 1830.
the sum of 2 plus 2 is 4/2+2=44
1 + 2 + 4 + ... + 2n = 2n+1 - 1