Answer:
a : c = 6 : 5
Step-by-step explanation:
Expressing the ratios in fractional form, then
[tex]\frac{a}{c}[/tex] = [tex]\frac{a}{b}[/tex] × [tex]\frac{b}{d}[/tex] × [tex]\frac{d}{c}[/tex] = [tex]\frac{1}{2}[/tex] × [tex]\frac{4}{5}[/tex] × [tex]\frac{3}{1}[/tex] = [tex]\frac{12}{10}[/tex] = [tex]\frac{6}{5}[/tex]
Thus a : c = 6 : 5