Question

tính \(\frac{3}{4}.\frac{8}{9}.......\frac{899}{900}\)

Answer 1

A=31/60

Answer 2

mk chỉ lớp 6 thui nên ko trả lời được sory

Answer 3

Đặt \(S=\frac{3}{4}.\frac{8}{9}.........\frac{899}{900}\)

\(\Rightarrow S=\frac{1.3}{2^2}.\frac{2.4}{3^2}.........\frac{29.31}{30^2}\)

\(S=\frac{\left(1.3\right).\left(2.4\right)........\left(29.31\right)}{\left(2.2\right).\left(3.3\right)..........\left(30.30\right)}=\frac{\left(1.2.3.......29\right).\left(3.4.........31\right)}{\left(2.3..........30\right).\left(2.3.........30\right)}\)

\(S=\frac{1.2.3......29}{2.3........30}.\frac{3.4.........31}{2.3..........30}=\frac{1}{30}.\frac{31}{2}=\frac{31}{60}\)