Question

Выполните сложение: 3+1 1/5 ; 1 3/7+2 5/7 ; 5 2/5+3 2/9

Answer 1

Ответ:

1) $3 + 1\frac{1}{5} = 3 + 1 + \frac{1}{5} = 4 + \frac{1}{5} = 4\frac{1}{5} = \frac{21}{5} = 4,2$

2) $1\frac{3}{7} +2\frac{5}{7} = (1 +2) + (\frac{3}{7} +\frac{5}{7} ) = 3 + \frac{8}{7} = 3 +\frac{1}{7} = 3 + 1 + \frac{1}{7} = 4 +\frac{1}{7} = 4\frac{1}{7} = \frac{29}{7}$

3) $5\frac{2}{5} + 3 \frac{2}{9} = (5 +3) + (\frac{2}{5} +\frac{2}{9}) = 8+ \frac{28}{45} = 8\frac{28}{45} = \frac{388}{45}$