Bonjour,
Exercice 17 :
a) [tex]\frac{21}{14} =\frac{21/7}{14/7} =\frac{3}{2}[/tex]
b) [tex]\frac{8}{10} = \frac{8/2}{10/2} =\frac{4}{5}[/tex]
c) [tex]\frac{14}{21} =\frac{14/7}{21/7}=\frac{2}{3}[/tex]
Exercice 18 :
a) [tex]\frac{15}{20} =\frac{15/5}{20/5} =\frac{3}{4}[/tex]
b) [tex]\frac{10}{30}=\frac{10/10}{30/10} =\frac{1}{3}[/tex]
c) [tex]\frac{16}{12} =\frac{16/4}{12/4} =\frac{4}{3}[/tex]
exercice 19 :
a) [tex]\frac{27}{36} =\frac{27/9}{36/9}=\frac{3}{4}[/tex]
b) [tex]\frac{56}{49}=\frac{56/7}{49/7} =\frac{8}{7}[/tex]
c) [tex]\frac{64}{72} =\frac{64/8}{72/8} =\frac{8}{9}[/tex]
Exercice 20 :
a) [tex]\frac{44}{33} =\frac{44/11}{33/11} =\frac{4}{3}[/tex]
b) [tex]\frac{32}{56} =\frac{32/8}{56/8}=\frac{4}{7} }[/tex]
c) [tex]\frac{5}{25} =\frac{5/5}{25/5} =\frac{1}{5}[/tex]
Exercice 21 :
a) [tex]\frac{10}{100}=\frac{10/10}{100/10} =\frac{1}{10}[/tex]
b) [tex]\frac{26}{39} =\frac{26/13}{39/13} =\frac{2}{3}[/tex]
c) [tex]\frac{24}{6} =\frac{24/6}{6/6} =\frac{4}{1}[/tex]
Exercice 22 :
a) [tex]180:90=\frac{180}{90} =\frac{9*20}{9*10} =\frac{20}{10} =20:10=2[/tex]
b) [tex]117:18=\frac{117}{18} =\frac{9*13}{9*2} =\frac{13}{2} =13:2=6,5[/tex]
c) [tex]55:25=\frac{55}{25}=\frac{5*11}{5*5} =\frac{11}{5} =11:5=2,2[/tex]
Bonne journée et surtout, prends bien soin de toi ;)
