Giải câu 4 trang 13 VEN toán 5 tập 1

$\frac{4}{3}\times \frac{9}{10}=\frac{2\times \not{2}\times 3\times \not{3}}{\not{3}\times 5\times \not{2}}=\frac{6}{5}$

$\frac{9}{16} :\frac{27}{8}=\frac{9}{16}\times \frac{8}{27}=\frac{\not{9}\times \not{8}}{2\times \not{8}\times 3\times \not{9}}=\frac{1}{6}$

$\frac{40}{7}: \frac{5}{14}=\frac{40}{7}\times \frac{14}{5}=\frac{8\times \not{5}\times 2\times \not{7}}{\not{7}\times \not{5}}=\frac{16}{1}= 16$