a. 1,2 : 3,24 = \(\frac{1,2}{3,24}\)= \(\frac{120}{324}\)=\(\frac{120:12}{324:12}\)=\(\frac{10}{27}\)
b. 215 : 34215 : 34 = \(\frac{215}{34215}\). \(\frac{1}{34}\)=\(\frac{43}{6843}\).\(\frac{1}{34}\)=\(\frac{43}{232662}\)
c. 27 : 0,42 = 27 : \(\frac{42}{100}\)= 27 : \(\frac{21}{50}\)= 27 . \(\frac{50}{21}\)= \(\frac{27.50}{21}\)=\(\frac{9.50}{7}\)=\(\frac{450}{7}\)