Question

Обчислити: а)1/3+4/5; б)6/7-3/5 ; в)1/27+(7/9-2/3); г)17/20-(3/5-1/4)



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Answer 1

Ответ:

Пошаговое объяснение:

$\frac{1}{3} +\frac{4}{5}= \frac{5}{15} +\frac{12}{15}= \frac{17}{15} =1\frac{2}{15} \\ \\ \frac{6}{7} -\frac{3}{5} =\frac{30}{35} -\frac{21}{35} =\frac{9}{35}\\ \\ \frac{1}{27}+(\frac{7}{9}-\frac{2}{3} )= \frac{1}{27}+(\frac{21}{27}-\frac{18}{27} )=\frac{1}{27} +\frac{3}{27} =\frac{4}{24} \\ \\ \frac{17}{20}-(\frac{3}{5} -\frac{1}{4})= \frac{17}{20}-(\frac{12}{20} -\frac{5}{20})= \frac{17}{20} -\frac{7}{20} =\frac{10}{20}=\frac{1}{2}$