a) \( \dfrac{14}{70} =\dfrac{14:7}{70:7}=\dfrac{2}{10}\) ;
b) \( \dfrac{11}{25} =\dfrac{11 \times 4}{25 \times 4}=\dfrac{44}{100}\) ;
c) \( \dfrac{75}{300} =\dfrac{75:3}{300:3}=\dfrac{25}{100}\) ;
d) \( \dfrac{23}{500}=\dfrac{23 \times 2}{500 \times 2}=\dfrac{46}{1000}\).