Which pair of ratios is not equal? 72 : 64 and 27 : 4 72 : 64 and 27 : 4 90 to 18 and 5 to 1 90 to 18 and 5 to 1 25 to 10 and 10 to 4 25 to 10 and 10 to 4 6 : 7 and 30 : 35