Вычислите 1)5 5/7*9/20 2)2 1/4:1 1/8 3)-5 1/2*(-8 1/11) 4)-3 5/9*4 7/8 5)1,2+3/7...

1. $5 \frac{5}{7}* \frac{9}{20} = \frac{40}{7} * \frac{9}{20} = \frac{2*9}{7} = \frac{18}{7} = 2\frac{4}{7}$
2. $2 \frac{1}{4} :1 \frac{1}{8} = \frac{9}{4} : \frac{9}{8} = \frac{9}{4} * \frac{8}{9}= 2$
3. $-5\frac{1}{2} *( -8\frac{1}{11} )= \frac{11}{2} * \frac{89}{11} = \frac{89}{2} = 44\frac{1}{2}$
4. $-3 \frac{5}{9} *4 \frac{7}{8} =- \frac{32}{9} * \frac{39}{8} =- \frac{4*39}{9}= -\frac{156}{9}=-17 \frac{3}{9}=-17 \frac{1}{3}$
5. $1,2+ \frac{3}{7} =1 \frac{2}{10}+ \frac{3}{7}= \frac{12}{10} + \frac{3}{7} = \frac{84}{70} + \frac{30}{70}= \frac{114}{70}= 1 \frac{44}{70}= \frac{22}{35}$
6. $-0,4+ \frac{5}{6} =- \frac{4}{10} + \frac{5}{6} =- \frac{24}{60} + \frac{50}{60}= \frac{26}{60}= \frac{13}{35}$