What are the three ratios equivalent to 8: 12

2/3- divide both numerator and denominator by its common factors which in this case is 4 (following this would get you 2/3)
4/6- divide both numerator and denominator by its common factor which in this case is 2 (following this would get you 4/6)
16/24- multiply both the numerator and denominator by 2