Question

Tính:

a) \(\dfrac{2}{3}+\dfrac{3}{5}\);                                \(\dfrac{7}{12}-\dfrac{2}{7}+\dfrac{1}{12}\);                                \(\dfrac{12}{17}-\dfrac{5}{17}-\dfrac{4}{17}\).

b) \(578,69+281,78\);                             \(594,72+406,38+329,47\).

Answer 1

a) \(\dfrac{2}{3}+\dfrac{3}{5}=\dfrac{10}{15}+\dfrac{9}{15}=\dfrac{19}{15}\)

Answer 2

a) \(\dfrac{7}{12}-\dfrac{2}{7}+\dfrac{1}{12}=\dfrac{2}{3}-\dfrac{2}{7}=\dfrac{14}{21}-\dfrac{6}{21}=\dfrac{8}{21}\)

Answer 3

a) \(\dfrac{12}{17}-\dfrac{5}{17}-\dfrac{4}{17}=\dfrac{12-5-4}{17}=\dfrac{3}{17}\)

Answer 4

b) \(578,69+281,78=860,47\)

Answer 5

b) \(594,72+406,38+329,47=1001,1+329,47=1330,57\)