Răspuns:
Explicație pas cu pas:
4. a) [tex]2\frac{1}{3} * \frac{7}{5} = \frac{2*3+1}{3} * \frac{7}{5} = \frac{7}{3} * \frac{7}{5} = \frac{49}{15}[/tex]
b) [tex]\frac{5}{9} * 1\frac{10}{13} = \frac{5}{9} * \frac{1*13+10}{13} = \frac{5}{3} * \frac{23}{13} = \frac{115}{39}[/tex]
c) [tex]2\frac{3}{4} * \frac{4}{9} = \frac{2*4+3}{4} * \frac{4}{9} = \frac{11}{4} * \frac{4}{9} = \frac{11}{9}[/tex]
d) [tex]4\frac{2}{3} * \frac{2}{5} = \frac{4*3+2}{4} * \frac{2}{5} = \frac{14}{3} * \frac{2}{5} = \frac{28}{15}[/tex]
e) [tex]2\frac{3}{4} * \frac{4}{11} = \frac{2*4+3}{4} * \frac{4}{11} = \frac{11}{4} * \frac{4}{11} = \frac{44}{44} = 1[/tex]
f) [tex]2\frac{7}{3} * \frac{9}{2} = \frac{2*3+7}{3} * \frac{9}{2} = \frac{13}{3} * \frac{9}{2} = \frac{117}{6}[/tex]
g) [tex]3\frac{5}{6} * \frac{30}{23} = \frac{3*6+5}{6} * \frac{30}{23} = \frac{23}{6} * \frac{30}{23} = \frac{30}{6} = 5[/tex]
6. a) [tex]2\frac{1}{4} * \frac{7}{3}*6 = \frac{2*4+1}{4} * \frac{7}{3}*6= \frac{9}{4} * \frac{7}{3}*6 = \frac{63}{12}*6 = \frac{21}{4}*6 = \frac{126}{4} = \frac{63}{2}[/tex]
b) [tex]\frac{7}{8} * 1\frac{3}{5}*4= \frac{7}{8} * \frac{1*5+3}{5}*4= \frac{7}{8} * \frac{8}{5}*4 = \frac{56}{40}*4 = \frac{224}{40} = \frac{112}{20} = \frac{56}{10} = \frac{28}{5}[/tex]
c) [tex]\frac{5}{3} * \frac{6}{10}*8 = \frac{30}{30} *8 = \frac{1}{1}*8= \frac{8}{1} = 8[/tex]
d) [tex]\frac{9}{25} * 2\frac{1}{2} * 1\frac{5}{9}= \frac{9}{25} * \frac{2*2+1}{2} * \frac{1*9+5}{9} = \frac{9}{25} * \frac{5}{2} * \frac{14}{9} = \frac{2}{5}[/tex]
e) [tex]\frac{13}{15} * \frac{5}{8} * 2\frac{2}{7} = \frac{13}{15} * \frac{5}{8} * \frac{2*7+2}{7} = \frac{13}{15} * \frac{5}{8} * \frac{16}{7} = \frac{26}{21}[/tex]
