Вычислите, используя законы сложения:
а) $\frac{11}{48} + \frac{13}{48} + \frac{17}{48}$;
б) $\frac{19}{55} + \frac{18}{55} + \frac{12}{55}$;
в) $\frac{25}{64} + \frac{17}{64} + \frac{15}{64}$;
г) $\frac{23}{69} + \frac{38}{69} + \frac{7}{69}$;
д) $\frac{28}{43} + \frac{52}{43} + \frac{19}{43}$;
е) $\frac{17}{45} + \frac{11}{45} + \frac{23}{45}$;
ж) $\frac{1}{45} + \frac{2}{45} + \frac{7}{45}$;
з) $\frac{13}{44} + \frac{15}{44} + \frac{17}{44}$;
и) $\frac{16}{77} + \frac{8}{77} + \frac{4}{77}$.
$\frac{11}{48} + \frac{13}{48} + \frac{17}{48} = \frac{11}{48} + (\frac{13}{48} + \frac{17}{48}) = \frac{11}{48} + \frac{30}{48} = \frac{41}{48}$
$\frac{19}{55} + \frac{18}{55} + \frac{12}{55} = \frac{19}{55} + (\frac{18}{55} + \frac{12}{55}) = \frac{19}{55} + \frac{30}{55} = \frac{49}{55}$
$\frac{25}{64} + \frac{17}{64} + \frac{15}{64} = (\frac{25}{64} + \frac{15}{64}) + \frac{17}{64} = \frac{40}{64} + \frac{17}{64} = \frac{57}{64}$
$\frac{23}{69} + \frac{38}{69} + \frac{7}{69} = (\frac{23}{69} + \frac{7}{69}) + \frac{38}{69} = \frac{30}{69} + \frac{38}{69} = \frac{68}{69}$
$\frac{28}{43} + \frac{52}{43} + \frac{19}{43} = (\frac{28}{43} + \frac{52}{43}) + \frac{19}{43} = \frac{80}{43} + \frac{19}{43} = \frac{99}{43}$
$\frac{17}{45} + \frac{11}{45} + \frac{23}{45} = (\frac{17}{45} + \frac{23}{45}) + \frac{11}{45} = \frac{40}{45} + \frac{11}{45} = \frac{51}{45} = \frac{17 * 3}{15 * 3} = \frac{17}{15}$
$\frac{1}{45} + \frac{2}{45} + \frac{7}{45} = (\frac{1}{45} + \frac{2}{45}) + \frac{7}{45} = \frac{3}{45} + \frac{7}{45} = \frac{10}{45} = \frac{2 * 5}{9 * 5} = \frac{2}{9}$
$\frac{13}{44} + \frac{15}{44} + \frac{17}{44} = (\frac{13}{44} + \frac{17}{44}) + \frac{15}{44} = \frac{30}{44} + \frac{15}{44} = \frac{45}{44}$
$\frac{16}{77} + \frac{8}{77} + \frac{4}{77} = (\frac{16}{77} + \frac{4}{77}) + \frac{8}{77} = \frac{20}{77} + \frac{8}{77} = \frac{28}{77} = \frac{4 * 7}{11 * 7} = \frac{4}{11}$
Пожауйста, оцените решение