Răspuns:
a) [tex]\frac{a}{19} + \frac{11a}{19} +\frac{7a}{19}[/tex]= [tex]\frac{a+11a+7a}{19} = \frac{19a}{19}[/tex]= a ( se adună numărătorii deoarece fractiile au același numitor 19)
b) [tex]\frac{3a+17a+ 26a}{23}[/tex]= [tex]\frac{46a}{23} = 2a[/tex]
c) [tex]\frac{11x+13x+25x}{49}[/tex]= [tex]\frac{24x+25x}{49} = \frac{49x}{49}[/tex]= x
d) [tex]\frac{15b-3b- 5b}{7} = \frac{15b-8b}{7}[/tex]= [tex]\frac{7b}{7} =b[/tex]
e) [tex]\frac{21y-7y-3y}{11}[/tex]= [tex]\frac{11y}{11}[/tex]= y
f) [tex]\frac{29c- 21c -8c }{47}[/tex]= [tex]\frac{0c}{47} =0[/tex]
a) [tex]\frac{1}{2} + \frac{5}{4} =[/tex][tex]\frac{2*1+5}{4} = \frac{2+5}{4} =\frac{7}{4}[/tex] se aduce la acelasi numitor 4
b) [tex]\frac{1}{9} + \frac{3}{7} =[/tex][tex]\frac{7*1+3*9}{7*9}[/tex]= [tex]\frac{7+27}{63}[/tex]= [tex]\frac{34}{63}[/tex] se aduce la acelasi numitor 63
c)[tex]\frac{8*1+3*6}{48}[/tex]= [tex]\frac{8+18}{48}[/tex]= [tex]\frac{26}{48}[/tex]= [tex]\frac{13}{24}[/tex]
d)[tex]\frac{10*13+9}{117}[/tex]= [tex]\frac{130+9}{117}[/tex]= [tex]\frac{139}{117}[/tex]
