Question

Решите пожалуйста ʕ´•ᴥ•`ʔ
3) -3 7/10+(-4 5/21)
4) -3 3/7+7 9/14+(-4 5/21)

Answer 1

Ответ:

1. −7  197 /210  
2. -1/42

Пошаговое объяснение :

1 . $-3\frac{7}{10} + (-4\frac{5}{21} )= -3\frac{7}{10} - 4\frac{5}{21} = -\frac{3*10+7}{10} -\frac{4*21+5}{21} = -\frac{37}{10} -\frac{89}{21} = -\frac{21*37}{21*10} - \frac{10*89}{10*21} = -\frac{777}{210} - \frac{890}{210}= \frac{-777-890}{210} = -\frac{1667}{210}= - 7 \frac{147}{210}$

2. $-3\frac{3}{7} +7\frac{9}{14} = -\frac{3*7+3}{7} + \frac{7*14+9}{14} = -\frac{24}{7} + \frac{107}{14} = -\frac{2*24}{2*7}+ \frac{1*107}{1*14} = -\frac{48}{14} +\frac{107}{14} = -\frac{48+107}{14} = \frac{59}{14} = 4 \frac{3}{14}$

3. $4\frac{3}{14} +(4-\frac{5}{21} )= 4\frac{3}{14} - 4\frac{5}{21} = \frac{4*14+3}{14} -\frac{4*21+5}{21}=\frac{59}{14} -\frac{89}{21} =\frac{3*56}{14} -\frac{2*89}{2*21} = \frac{177}{42} -\frac{178}{42}=\frac{177-178}{42}= -\frac{1}{42}$