Answer:
2nd option
Step-by-step explanation:
The ratios on both sides must be equal
[tex]\frac{15}{6}[/tex] ( divide numerator/ denominator by 3 )
= [tex]\frac{5}{2}[/tex] ≠ [tex]\frac{3}{2}[/tex] , then not a proportion
[tex]\frac{4}{5}[/tex] ( multiply numerator/ denominator by 3 )
= [tex]\frac{12}{15}[/tex] , this is a proportion
[tex]\frac{9}{21}[/tex] ( divide numerator/ denominator by 3 )
= [tex]\frac{3}{7}[/tex] ≠ [tex]\frac{6}{7}[/tex] , then not a proportion
[tex]\frac{10}{16}[/tex] ( divide numerator/ denominator by 2 )
= [tex]\frac{5}{8}[/tex] ≠ [tex]\frac{2}{8}[/tex] , then not a proportion
