Question

cho: 

A=\(\frac{45}{7.16}+\frac{75}{16.31}+\frac{60}{31.43}+\frac{135}{43.70}\)

B=\(\frac{18}{7.13}+\frac{36}{12.25}+\frac{72}{25.49}+\frac{63}{49.70}\)

Tính tỉ số \(\frac{A}{B}\)

Answer 1

\(A=\frac{45}{7.16}+\frac{75}{16.31}+\frac{60}{31.43}+\frac{135}{43.70}\)

\(=5\left(\frac{1}{7}-\frac{1}{16}+\frac{1}{16}-\frac{1}{31}+\frac{1}{31}-\frac{1}{43}+\frac{1}{43}-\frac{1}{70}\right)\)

\(=5\left(\frac{1}{7}-\frac{1}{70}\right)\)

mk sửa đề B

\(B=\frac{18}{7.13}+\frac{36}{13.25}+\frac{72}{25.49}+\frac{63}{49.70}\)

\(=3\left(\frac{1}{7}-\frac{1}{13}+\frac{1}{13}-\frac{1}{25}+\frac{1}{25}-\frac{1}{49}+\frac{1}{49}-\frac{1}{70}\right)\)

\(=3\left(\frac{1}{7}-\frac{1}{70}\right)\)

Vậy  \(\frac{A}{B}=\frac{5\left(\frac{1}{7}-\frac{1}{70}\right)}{3\left(\frac{1}{7}-\frac{1}{70}\right)}=\frac{5}{3}\)