Question

7/15 : (6/10 + 8/3) + 19 * 2/31

Answer 1

Ответ:  $1\dfrac{80}{217}$

Решение:

$\displaystyle \frac{7}{15} : \bigg(\frac{6}{10} + \frac{8}{3} \bigg)+19 \cdot \frac{2}{31} =\frac{7}{15} : \bigg(\frac{18}{30} + 2\frac{20}{30} \bigg)+\frac{19 \cdot 2}{31}= \frac{7}{15} : 2\frac{38}{30} \bigg+\frac{38}{31}= \\\\= \frac{7}{15} : \frac{98}{30} + 1\frac{7}{31} =\frac{7 \cdot 30}{15 \cdot 98} + 1\frac{7}{31} =\frac{1}{7} + 1\frac{7}{31} =1\frac{31+49}{217} = 1\frac{80}{217}$