Are the ratios 30: 12 and 40: 16 equal if reduced?

Yes, borh ratios when reduced are 5:2. 30:12 is 5:2 because both are divisible by 6. 30/6=5 and 12/6=2. 40:16 is 5:2 because both are divisible by 8, 40/8=5 and 16/8=2

B. 2 1/2 feet. multiply 2.5 inches by 12 to get thirty inches then divide by 12 to get 2.5 feet