Question

\(A=\frac{3}{2.5}+\frac{3}{5.8}+...+\frac{3}{17.20}\)

trả lời nhanh mọi người ơi ?

Answer 1

A=1/2 -1/5 +1/5 -1/8+...+1/17 -1/20=1/2 -1/20=9/20

Answer 2

yeah!

mình làm đúng rồi

Answer 3

\(A=\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+...+\frac{1}{17}-\frac{1}{20}\)

\(A=\frac{1}{2}-\frac{1}{20}=\frac{9}{20}\)

Answer 4

\(\frac{27}{20}\)

Answer 5

x=27/20

Answer 6

\(A=\frac{3}{2.5}+\frac{3}{5.8}+...+\frac{3}{17.20}\)

\(A=\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+...+\frac{1}{17}-\frac{1}{20}\)

\(A=\frac{1}{2}-\frac{1}{20}\)

\(A=\frac{10}{20}-\frac{1}{20}\)

\(A=\frac{9}{20}\)

Answer 7

9/20 khong phai la 27/20

Answer 8

vậy thì 9/20 hay 27/20

Answer 9

3.(1/2-1/5+1/5-1/8+....+1/17-1/20)

=3.(1/2-1/20)

=3.9/20

=27/20

kết quả đúng là 27/20

Answer 10

A=\(\frac{3}{2.5}+\frac{3}{5.8}+...+\frac{3}{17.20}\)

A=\(\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+...+\frac{1}{17}-\frac{1}{20}\)

A=\(\frac{1}{2}-\frac{1}{20}\)

A=\(\frac{10}{20}-\frac{1}{20}\)

A=\(\frac{10-1}{20}\)

\(A=\frac{9}{20}\)

Answer 11

\(A=\frac{3}{2.5}+\frac{3}{5.8}+...+\frac{3}{17.20}\)

\(\Rightarrow A=\frac{1}{2}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+...+\frac{1}{17}-\frac{1}{20}\)

\(\Rightarrow A=\frac{1}{2}-\frac{1}{20}\)

\(\Rightarrow A=\frac{9}{20}\)