Question

Найди значения выражений и сравни их: 11/12*3 3/7: 1 1/21-(3 1/6-2 7/15): 1 2/5 и 51-(86,45: 24,7+1,25)*2,4-36,99

Answer 1

1 уравнение

$\frac{11}{12} *3 \frac{3}{7} : 1 \frac{1}{21} -(3 \frac{1}{6}-2 \frac{7}{15}):1 \frac{2}{5}$

преобразуем

$\frac{11}{12} * \frac{24}{7} : \frac{22}{21} -(\frac{19}{6}- \frac{37}{15}): \frac{7}{5}$

решим по действиям

$\frac{11}{12} * \frac{24}{7} : \frac{22}{21} -(\frac{19}{6}- \frac{37}{15}): \frac{7}{5} \\ \\ \frac{19}{6}- \frac{37}{15}= \frac{5*19-2*37}{30} = \frac{95-74}{30} = \frac{21}{30} \\ \\ \frac{21}{30}: \frac{7}{5}=\frac{21}{30}* \frac{5}{7}=\frac{3}{6}= \frac{1}{2} \\ \\ \frac{11}{12} * \frac{24}{7}= \frac{11}{1} * \frac{2}{7}= \frac{22}{7} \\ \\ \frac{22}{7}: \frac{22}{21}=\frac{22}{7}* \frac{21}{22}=3 \\ \\ 3-\frac{1}{2}=3-0,5=2,5$

2 уравнение

$51-(86,45:24,7+1,25)*2,4-36,99$

решим по действиям

$86,45:24,7=3,5 \\ \\ 3,5+1,25=4,75 \\ \\ 4,75*2,4=11,4 \\ \\ 51-11,4-36,99=39,6-36,99=2,61$

ответ: 2,5<2,61