Bonsoir ! J'espère vous aider !
Réponse :
n°47 :
[tex]a. 42 = 2*21\\21 = 3*7\\7 = 7*1\\\\42 = 2*3*7\\\\\\56 = 7*8\\8 = 2*4\\4 = 2*2\\2 = 2*1\\\\56 = 7*2*2*2\\\\\\\frac{42}{56} = \frac{2*3*7}{7*2*2*2} = \frac{3}{2*2} = \frac{3}4} \\\\\\b. 56 = 7*8\\8 = 2*4\\4 = 2*2\\2 = 2*1\\\\56 = 7*2*2*2\\\\\\60 = 5*12\\12 = 3*4\\4 = 2*2\\2 = 2*1\\\\60 = 5*3*2*2\\\\\\\frac{56}{60} = \frac{7*2*2*2}{5*3*2*2} = \frac{7*2}{5*3} = \frac{14}{15} \\\\\\c. 60 = 5*12\\12 = 3*4\\4 = 2*2\\2 = 2*1\\\\60 = 5*3*2*2\\[/tex]
[tex]c.60 = 5*12\\12 = 3*4\\4 = 2*2\\2 = 2*1\\\\60 = 5*3*2*2\\ \\\\42 = 2*21\\21 = 3*7\\7 = 7*1\\\\42 = 2*3*7\\\\\\\frac{60}{42} = \frac{5*3*2*2}{2*3*7} = \frac{5*2}{7} = \frac{10}{7}[/tex]
