1) 1/2+2/3+3/4+5/6 egal (6+8+9+10)/12 (aducem la numitorul comun) egal33/12 egal 2 intreg si 9/12
2) (1/2+1/3+1/6+1/12)+ 1/9 egal 13/12+1/9 egal 7/36
3) 1/2+1/2+1/8+1/16+1/32 egal 31/32
4)1/2+1/3+1/5+1/6+1/10+1/15+1/30 egal 40/30 egal 1 intreg si 10/30
1/2+1/3+1/6+1/12 )