4.a) 15/4+11/4=26/4=13/2
b. 31/12+21/4=31/12+63/12=94/12=47/6
c.5/2+11/3+19/4=30/12+44/12+57/12=131/12
9. a. [tex]3 \frac{3}{4}=3 \frac{6}{8}= \frac{30}{8}
7 \frac{1}{2} =7 \frac{4}{8} = \frac{60}{8}
\frac{30+60+43}{8} = \frac{133}{8}
[/tex]
b. 23/9+205/18+370/27=138/54+615/54+740/54=1493/54
c.31/9+5/9+86/27=91/27+15/27+86/27=192/27
d. La d aduci la acelasi numitor care e 2^5*7
e. Numitorul comun e 30
pentru a introduce intregii in fractie :
2[tex] \frac{3}{4} = \frac{2*4+3}{4} [/tex]
Sper ca ai inteles!
