Question

Добыча угля, преимущественно открытым производится в бассейне:

Answer 1

1)
$\frac{1}{5} +0,2* \frac{5}{7} = \frac{1}{5} + \frac{1}{5} * \frac{5}{7} = \frac{1}{5} + \frac{1}{7} = \frac{7+5}{35}= \frac{12}{35}$
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2)
$1,4* \frac{3}{4} - \frac{1}{9}=1 \frac{2}{5} * \frac{3}{4} - \frac{1}{9} = \frac{7}{5} * \frac{3}{4} - \frac{1}{9} = \frac{21}{20} - \frac{1}{9} = \frac{189-20}{180} = \frac{169}{180}$
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3)
$\frac{2}{9} *1 \frac{1}{2} +0,1= \frac{2}{9} * \frac{3}{2} + \frac{1}{10} = \frac{1}{3} + \frac{1}{10} = \frac{10+3}{30} = \frac{13}{30}$
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$(1 \frac{2}{5} - \frac{1}{3} )* \frac{5}{8} =( \frac{7}{5} - \frac{1}{3} )* \frac{5}{8} = \frac{7}{8} - \frac{5}{24} = \frac{21-5}{24} = \frac{16}{24} = \frac{2}{3}$
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$( \frac{1}{4} +0,2)* \frac{5}{8} =( \frac{1}{4} + \frac{1}{5} )* \frac{5}{8} =( \frac{5+4}{20} )* \frac{5}{8} = \frac{9}{20} * \frac{5}{8} = \frac{9}{32}$
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$\frac{3}{4} *(2,7+ \frac{11}{25} )= \frac{3}{4} *( \frac{27}{10} + \frac{11}{25} )= \frac{3}{4} *( \frac{135+22}{50} )= \frac{3}{4} * \frac{157}{50} = \frac{471}{200} =2 \frac{71}{200}$
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4)
$5,2* \frac{1}{13} = \frac{52}{10} * \frac{1}{13} = \frac{52}{130} = \frac{26}{65}$кг
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5)
$10 \frac{1}{5} * \frac{10}{17} = \frac{51}{5} * \frac{10}{17} = 6$га
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6)
$4,25*1 \frac{1}{7} = \frac{425}{100} * \frac{8}{7} = \frac{850}{175} =4 \frac{150}{175} =4 \frac{6}{7}$$M^{2}$
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