Question

tinh nhanh

4/1.5+4/5.9+4/9.13+...+4/21.25

Answer 1

4/1.5+4/5.9+4/9.13+....+4/21.25

=1-1/5+1/5-1/9+1/9-1/13+......+1/21-1/25

=1-1/25

=24/25

Tích đúng cho mình nha

Answer 2

\(\frac{4}{1.5}+\frac{4}{5.9}+\frac{4}{9.13}+....+\frac{4}{21.25}\)

\(=1-\frac{1}{5}+\frac{1}{5}-\frac{1}{9}+....+\frac{1}{21}-\frac{1}{25}\)

\(=1-\frac{1}{25}=\frac{24}{25}\)

Answer 3

\(\frac{4}{1.5}+\frac{4}{5.9}+\frac{4}{9.13}+...+\frac{4}{21.25}\)

=\(1-\frac{1}{5}+\frac{1}{5}-\frac{1}{9}+\frac{1}{9}-\frac{1}{13}+...+\frac{1}{21}-\frac{1}{25}\)

=\(1-\frac{1}{25}\)

=\(\frac{24}{25}\)

Chúc bạn học giỏi nha!!!