Câu 4: trang 149 - toán tiếng Anh:
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\(\frac{7}{12}\) ....\(\frac{5}{12}\) \(\frac{2}{5}\).....\(\frac{6}{15}\) \(\frac{7}{10}\)....\(\frac{7}{9}\)
Bài Làm:
\(\frac{7}{12}\) and \(\frac{5}{12}\) have a comon deniminator 12 and 7 > 5 so \(\frac{7}{12}\) > \(\frac{5}{12}\)
\(\frac{7}{12}\) và \(\frac{5}{12}\) có cùng mẫu số 12 mà tử số 7 > 5 nên \(\frac{7}{12}\) > \(\frac{5}{12}\)
\(\frac{2}{5}\) = \(\frac{2 \times 3}{5 \times 3}\) = \(\frac{6}{15}\)
So \(\frac{2}{5}\) = \(\frac{6}{15}\)
Vậy \(\frac{2}{5}\) = \(\frac{6}{15}\)
\(\frac{7}{10}\) = \(\frac{7 \times 9}{10 \times 9}\) = \(\frac{63}{90}\)
\(\frac{7}{9}\) = \(\frac{7 \times 10}{9 \times 10}\) = \(\frac{70}{90}\)
So: \(\frac{7}{10}\) < \(\frac{7}{9}\)