Răspuns:
Ex. 5)
[tex]a) 1\frac{5}{7}*(2\frac{1}{3} -1\frac{3}{4})=\frac{12}{7}*(\frac{7}{3}-\frac{7}{4})=\frac{12}{7}*(\frac{7*4-7*3}{12})=\frac{28-21}{7} =\frac{7}{7} =1[/tex]
[tex]b)1\frac{1}{3}+1\frac{2}{13} *(3\frac{2}{5}-1\frac{2}{3})=\frac{4}{3}+\frac{15}{13}*(\frac{17}{5}-\frac{5}{3})=\frac{4}{3}+\frac{15}{13} *(\frac{17*3-5*5}{15}) =\frac{4}{3}+\frac{15}{13}*\frac{26}{15}[/tex]
[tex]=\frac{4}{3} +2 =\frac{4+2*3}{3}=\frac{10}{3}[/tex]
c) [tex]11\frac{3}{8}-(2\frac{5}{6}-1\frac{3}{8})*1\frac{5}{7}= \frac{91}{8}-( \frac{17}{6}- \frac{11}{8})*\frac{12}{7}=\frac{91}{8}-\frac{35}{24}*\frac{12}{7} =\frac{71}{8}[/tex]
[tex]d) 3\frac{2}{3} -\frac{3}{17}*(3\frac{2}{7}-1\frac{2}{3})= \frac{11}{3}-\frac{3}{17} *\frac{34}{21}=\frac{11}{3}- \frac{2}{7}=\frac{11*7-2*3}{21}= \frac{71}{21}[/tex]
Def: Un Intreg înseamnă o fractie care are acelasi număr si la numitor si la numarator , de exemplu [tex]\frac{6}{6},\frac{3}{3},\frac{256}{256} ,\frac{x}{x}[/tex]
