a) -13/144 + 17/108 = aducem la acelasi numitor
calculam [144,108]=2^4·3³=16·27=432 este numitorul comun
144=2^4·3²
108=2²·3³
432:144=3 amplificam I fractie
432:108=4 amplificam a doua fractie
vom avea:
(-13·3)/432+(17·4)/432=-39/432+68/432=29/432
asa se calculeaza si restul
b) (-11/48) + (-13/72) + 59/144 =(-11·3-13·2+59)/144=(-33-26+59)/144=0
c) 2323/3232 + (- 4242/2424) =(3·2323-4·4242)/9696=(6969-16968)/9696=9999/9696 simplif.cu 3=3333/3232=1,03125
d) (-123123/222222) + (-41041/74074)=(-123123-41041·3)/222222=
(-123123-123123)/222222=-246246/222222=simplificam cu 6=-41041/37037=-1,(108)
