Question

1) $a) \frac{3}{5} + \frac{5}{12} ; b) \frac{3}{7} + \frac{7}{10} ; c) \frac{1}{4} + \frac{7}{13} ; d) \frac{3}{4} + \frac{7}{15} ; e) \frac{2}{5} + \frac{3}{16} ; f) \frac{4}{9} + \frac{5}{11} ;$
2) $a) \frac{3}{11} + \frac{1}{10} ; b) \frac{1}{13} + \frac{1}{10} ; c) \frac{1}{17} + \frac{1}{10} ; d) \frac{1}{19} + \frac{1}{20} ; e) \frac{1}{13} + \frac{1}{30} ; f) \frac{1}{29} + \frac{1}{10} ;$
3) $a) \frac{1}{4} + \frac{1}{16} + \frac{1}{64}; b) \frac{1}{5} + \frac{1}{25} + \frac{1}{125} ; c) \frac{1}{6} + \frac{1}{36} + \frac{1}{216} ; d) \frac{1}{7} + \frac{1}{49} + \frac{1}{343} ;$

Answer 1

Acest tip de exercitii se rezolva, aducand fractiile la acelasi numitor.
1.
a)(12x3+5x5)/(5x12)=(36+25)/60=61/60
b)(10x3+7x7)/(7x10)=(30+49)/70=79/70
c)(13x1+4x7)/(4x13)=(13+28)/52=41/52
d)(15x3+4x7)/(4x15)=(45+28)/60=73/60
e)(16x2+5x3)/(16x5)=(32+15)/80=47/80
f)(11x4+5x9)/(9x11)=(44+45)/99=89/99

2. Se rezolva identic, numitorul comun fiind produsul celor doi numitor.

3.Aici numitorul comun este c.m.m.m.c al numitorilor fractiilor
Ex. pentru a)
4=2²
16=2⁴
______
c.m.m.m.c=2⁴=16
=>Fractiile se aduc la numitorul comun 16.
(4x1+1)/16=5/16
b)Numitorul comun este 125
(25x1+5x1+1)/125=31/125
c)Numitorul comun este 216
(36x1+6x1+1)/216=43/216
d)Numitorul comun este 343
(49x1+7x1+1)/343=57/343