Question

Tính 6/7+7/8 c 4/5-2/3 g 1/5:2/7 d 4/7-11/42 b 2/3+3/51

Answer 1

\(\dfrac{6}{7}+\dfrac{7}{8}=\dfrac{48}{56}+\dfrac{49}{56}=\dfrac{97}{56}\)

\(\dfrac{4}{5}-\dfrac{2}{3}=\dfrac{12}{15}-\dfrac{10}{15}=\dfrac{2}{15}\)

\(\dfrac{1}{5}:\dfrac{2}{7}=\dfrac{1}{5}.\dfrac{7}{2}=\dfrac{7}{10}\)

\(\dfrac{4}{7}-\dfrac{11}{42}=\dfrac{24}{42}-\dfrac{11}{42}=\dfrac{13}{42}\)

\(\dfrac{2}{3}+\dfrac{3}{51}=\dfrac{34}{51}+\dfrac{3}{51}=\dfrac{37}{51}\)

Answer 2

Tính

\(\dfrac{6}{7}+\dfrac{7}{8}=\dfrac{48}{56}+\dfrac{49}{56}=\dfrac{48+49}{56}=\dfrac{97}{56}\)

\(\dfrac{4}{5}-\dfrac{2}{3}=\dfrac{12}{15}-\dfrac{10}{15}=\dfrac{12-10}{15}=\dfrac{2}{15}\)

\(\dfrac{1}{5}:\dfrac{2}{7}=\dfrac{1}{5}.\dfrac{7}{2}=\dfrac{1.7}{5.2}=\dfrac{7}{10}\)

\(\dfrac{4}{7}-\dfrac{11}{42}=\dfrac{24}{42}-\dfrac{1}{42}=\dfrac{24-1}{42}=\dfrac{23}{42}\)

\(\dfrac{2}{3}+\dfrac{3}{51}=\dfrac{34}{51}+\dfrac{3}{51}=\dfrac{34+3}{51}=\dfrac{37}{51}\)

Answer 3

a) \(\dfrac{6}{7}+\dfrac{7}{8}=\dfrac{48}{56}+\dfrac{49}{56}=\dfrac{97}{56}\)

c) \(\dfrac{4}{5}-\dfrac{2}{3}=\dfrac{12}{15}-\dfrac{10}{15}=\dfrac{2}{15}\)

g) \(\dfrac{1}{5}:\dfrac{2}{7}=\dfrac{1}{5}\cdot\dfrac{7}{2}=\dfrac{7}{10}\)

d) \(\dfrac{4}{7}-\dfrac{11}{42}=\dfrac{24}{42}-\dfrac{11}{42}=\dfrac{13}{42}\)

b) \(\dfrac{2}{3}+\dfrac{3}{51}=\dfrac{34}{51}+\dfrac{3}{51}=\dfrac{37}{51}\)