Question

Exercițiile 8 9 și 10 vă rog nu mai am puncte și de fiind de media mea la matematică această teamă

Answer 1

Răspuns:

8. $\frac{75*5+3}{5}$= $\frac{378}{5}$     $\frac{4*5+1}{5}$= $\frac{21}{5}$  

$\frac{378}{5}$ : $\frac{21}{5}$ = $\frac{3*126}{5} * \frac{5}{3*7}$ = $\frac{126}{7}$= 18  parcari

9. - 4,2(6)= $\frac{426-42}{90} = \frac{384}{90} = -\frac{64}{15}$

$-\frac{64}{10}$ : a= $-\frac{64}{15}$

a= $\frac{64}{15} *\frac{10}{64}$= $\frac{10}{15} = \frac{2*5}{3*5}$= $\frac{2}{3}$  (impartitorul)    (-a) *(-b)= c      -a*b= -c

10. a)  $\frac{3}{4} *\frac{2}{1}$= $\frac{3}{2}$      $\frac{4}{3} *\frac{3*9}{2*4}$= $\frac{9}{2}$

$\frac{3}{2} : \frac{9}{2} : \frac{5}{9}$ = $\frac{3}{2} * \frac{2}{9} * \frac{9}{5}$  = $\frac{3}{5}$

b) $\frac{9}{8} *\frac{2}{3}$ = $\frac{3}{4}$    $\frac{6}{5} *\frac{5}{3*6}$= $\frac{1}{3}$  

$\frac{3}{4} : \frac{1}{2} : \frac{3}{2}$= $\frac{3}{4}* \frac{2}{1} * \frac{2}{3}$ = $\frac{3*4}{4*1*3}$ = 1

c) $\frac{9}{10} * \frac{2}{3}$ = $\frac{3}{5}$     $\frac{16}{15} * \frac{3}{2}$= $\frac{8}{5}$

$\frac{3}{5} : \frac{8}{5} : \frac{3}{4}$ = $\frac{3}{5} *\frac{5}{2*4}* \frac{4}{3}$ = $\frac{1}{2}$