Question

Tính \(2.5+1.4-1\dfrac{3}{7}\)

Answer 1

\(2.5+1.4-1\dfrac{3}{7}=\dfrac{5}{2}+\dfrac{7}{5}-\dfrac{10}{7}=\dfrac{5\cdot35}{2\cdot35}+\dfrac{7\cdot14}{5\cdot14}-\dfrac{10\cdot10}{7\cdot10}=\dfrac{175}{70}+\dfrac{98}{70}-\dfrac{100}{70}=\dfrac{173}{70}\)

Answer 2

\(=3,9+\dfrac{10}{7}=\dfrac{39}{10}+\dfrac{10}{7}=\dfrac{173}{70}\)

Answer 3

2,5 + 1,4 - \(1\dfrac{3}{7}\)

=3,9 + \(\dfrac{10}{7}\)

=\(\dfrac{373}{70}\)