Question

Aduceti la acelasi numitor comun:

7) $\frac{1}{4}$ + $\frac{7}{24}$ + $\frac{5}{8}$
8) $\frac{1}{5} + \frac{7}{15} + \frac{2}{9}$
9) $\frac{3}{20} + \frac{17}{180} + \frac{4}{9} + \frac{23}{15}$
10)$\frac{1}{3} + \frac{7}{18} + \frac{5}{9}$
11) $\frac{3}{20} + \frac{47}{180} + \frac{7}{15} + \frac{23}{60}$
12) $\frac{3}{25} + \frac{7}{60} + \frac{11}{50} + \frac{13}{100}$

Answer 1

7.  1/4+7/24+5/8=
numitor comun 24
=(1*6+7+5*3)/24=28/24=7/6

8. 1/5+7/15+2/3
numitor comun 15
=(1*3+7+2*5)/15=20/15=4/3

9. 3/20+17/180+4/9+23/15
numitor comun 180
=(3*9+17+4*20+23*12)/180=
=(27+17+80+276)/180=400/180=40/18=20/9

10.1/3+7/18+5/9
numitor comun 18
=(1*6+7+5*2)/18=(6+7+10)/18=23/18

11. 3/20+47/180+7/15+23/60
numitor comun 180
=(3*9+47+7*12+23*3)/180=
=(27+47+84+69)/180=227/180

12.3/25+7/60+11/50+13/100=
numitor comun 300
=(3*12+7*5+11*6+13*3)/300=
=(36+35+66+39)/300=176/300=44/75