Question

Ajutor!!!
dau coroana

Answer 1

(1/2+2/3-1/4)-(2/5+1/4-1/2)=
=1/2+2/3-1/4-2/5-1/4+1/2=
=2/2+2/3-2/4-2/5=                                 numitor comun 60
=(60+40-30-24)/60=
=46/60=
=23/30=0,7(6)

10*[1/2+(7/12-1/8):5/7]=
=10*[1/2+(14/24-3/24):5/7]=
=10*(1/2+11/24 *7/5)=
=10*(1/2+77/120)=
=10*(60/120+77/120)=
=10*137/120=
=137/12=
=11,41(6)

(1+1/2)/(1-1/2) * (2/5+3/4)/(4/5-2/3)=
=(3/2*2) * [(8+15)/20] /[(12-10)/15]=
=3 * (23/20) /(2/15)=
=3 * 23/20 *15/2=
=3 * 23/4 *3/2=
=207/8=25,875

Answer 2

(1/2+2/3-1/4)-(2/5+1/4-1/2)=
(6+4-3)/12-(8+5-10)/20=
7/12-3/20=(42-15)/60=27/60=9/20