Question

[anh chàng đẹp trai]

tính bằng cách thuận tiện nhất:

a,\(\frac{3}{5}\)*\(\frac{8}{27}\)*\(\frac{5}{3}\)

b,\(\frac{7}{19}\)*\(\frac{1}{3}\)+\(\frac{7}{19}\)*\(\frac{2}{3}\)

ai đúng cho 2 tích

Answer 1

[Nguyen tien linh]

=7/9*[1/3+2/3]=7/9*1=7/9

Answer 2

[KAl(SO4)2·12H2O]

a) \(\frac{3}{5}\times\frac{8}{27}\times\frac{5}{3}\)

\(=\left(\frac{3}{5}\times\frac{5}{3}\right)\times\frac{8}{27}\)

\(=1\times\frac{8}{27}\)

\(=\frac{8}{27}\)

b) \(\frac{7}{19}\times\frac{1}{3}+\frac{7}{19}\times\frac{2}{3}\)

\(=\frac{7}{19}\times\left(\frac{1}{3}+\frac{2}{3}\right)\)

\(=\frac{7}{19}\times1\)

\(=\frac{7}{19}\)