Question

Tính :

a) 5 / 6 x 6 / 7 x 7 / 8 : 15 / 16

b) 4 / 7 x 7 / 10 x 3 / 4 : 9 / 20

Answer 1

#) Giải :

a) \(\frac{5}{6}\)x  \(\frac{6}{7}\)x  \(\frac{7}{8}\):  \(\frac{15}{16}\)=  \(\frac{5}{8}\):   \(\frac{15}{16}\)=  \(\frac{5}{8}\)x   \(\frac{16}{15}\)=  \(\frac{80}{120}\)=  \(\frac{4}{5}\)

b) \(\frac{4}{7}\)x  \(\frac{7}{10}\)x   \(\frac{3}{4}\) :  \(\frac{9}{20}\)=  \(\frac{2}{5}\)x   \(\frac{3}{4}\): \(\frac{9}{20}\)=  \(\frac{3}{10}\):  \(\frac{9}{20}\)=  \(\frac{60}{90}\)= \(\frac{2}{3}\)

#) Chúc bn học tốt :D

Answer 2

\(=\frac{5x6x7}{6x7x8}x\frac{16}{15}\\ =\frac{5}{8}x\frac{16}{15}\\ =\frac{2}{3}\)

b)\(=\frac{4x7x3}{7x10x4}x\frac{20}{9}\\ =\frac{3}{10}x\frac{20}{9}\\ =\frac{2}{3}\)