Question

Решить, ответ записать десятичной дробью.

Answer 1

10.05

Пошаговое объяснение:

$2\frac{1}{2} +2\frac{21}{30} +3\frac{3}{5} +1\frac{1}{4}$

1) $2\frac{1}{2} +2\frac{21}{30} =5\frac{1}{5}$  $\frac{2 * 2+1}{2} + \frac{2*30+21}{30} = \frac{5}{2} + \frac{81}{30} = \frac{15*5}{15*2} + \frac{1*81}{1*30} = \frac{75}{30} + \frac{81}{30} = \frac{81+75}{30} = \frac{156}{30} = \frac{26*6}{5*6} =\frac{26}{5} = 5\frac{1}{5}$

2) $5\frac{1}{5} +3 \frac{3}{5}=8 \frac{4}{5}$     $\frac{5*5+1}{5} + \frac{3*5+3}{5} = \frac{26}{5} +\frac{18}{5} =\frac{26+18}{5} =\frac{44}{5} = 8\frac{4}{5}$

3) $8\frac{4}{5} + 1\frac{1}{4} = 10\frac{1}{20}$ = 10.05     $\frac{8*5+4}{5} + \frac{1*4+1}{4} =\frac{44}{5} + \frac{5}{4} = \frac{4*44}{4*5} +\frac{5*5}{5*4} =\frac{176}{20} + \frac{25}{20} = \frac{176+25}{20} = \frac{201}{20} =10 \frac{1}{20} =10.05$