Rút gọn các phân số sau: 45/54 ; 68/80 ; 62/76 ; 34/52 ; 24/40

$\dfrac{45}{54}=$ $\dfrac{5}{6}$

$\dfrac{68}{80}=$ $\dfrac{17}{20}$

$\dfrac{62}{76}=$ $\dfrac{31}{38}$

$\dfrac{34}{52}=$ $\dfrac{17}{26}$

$\dfrac{24}{40}=$ $\dfrac{4}{5}$