80= 5x5x3+5
37 + 43 = 80 2 + 3 + 5 + 23 + 47 = 80 2 + 7 + 11 + 17 + 43 = 80
3 x 3 x 3 = 27 2 x 2 x 2 x 3 x 3 = 72 5 x 7 = 35 2 x 2 x 2 x 2 x 5 = 80
11
1+2+3+5+11+17+41 = 80
Three of them.
-83
(-1)+(-2)=(-3) (-1)(-2)=2
392
-3 and 5
-5 and 3
4 + 1 - 2 = 3