Răspuns:
Explicație pas cu pas:
0,75 - 0,75*(19/10 - 1,5) = 0,75 - 0,75*(1,9 - 1,5) = 0,75 - 0,75*0,4
= 0,75 - 0,3 = 0,45
_____________
(1/3 + 0,25)(1 + 5/7) = (1/3 + 25/100)*(7/7 + 5/7) = (1/3 + 1/4)*12/7
= (4/12 + 3/12)*12/7 = 7/12*12/7 = 1
______________
2/5*(0,5 + 0,5*1/3) = 2/5*(5/10 + 5/10*1/3) = 2/5*(1/2 + 1/2*1/3)
= 2/5*(1/2 + 1/6) = 2/5*(3/6 + 1/6) = 2/5*4/6 = 8/30 = 4/15
