Question

Cộng và trừ những phân số sau:

12/6 + 15/7=?

12/13 - 8/9=?

43/54 + 76/8=?

giúp mình với trả lời mình tick cho nhé

Answer 1

\(\dfrac{12}{6}+\dfrac{15}{7}=\dfrac{84}{42}+\dfrac{90}{42}=\dfrac{174}{42}=\dfrac{29}{7}\)

\(\dfrac{12}{13}-\dfrac{8}{9}=\dfrac{108}{117}-\dfrac{104}{117}=\dfrac{4}{117}\)

\(\dfrac{43}{54}+\dfrac{76}{8}=\dfrac{344}{432}+\dfrac{4104}{432}=\dfrac{4448}{432}=\dfrac{278}{27}\)

Answer 2

\(\dfrac{12}{6}+\dfrac{15}{7}=2+\dfrac{15}{7}=\dfrac{14}{7}+\dfrac{15}{7}=\dfrac{29}{7}\\ \dfrac{12}{13}-\dfrac{8}{9}=\dfrac{108}{117}-\dfrac{104}{117}=\dfrac{4}{117}\\ \dfrac{43}{54}+\dfrac{76}{8}=\dfrac{43}{54}+\dfrac{19}{2}=\dfrac{43}{54}+\dfrac{513}{54}=\dfrac{556}{54}=\dfrac{278}{27}\)