Final answer:
The ratios are as follows: A+ blood to O+ blood is 2:1, A+ blood to total blood is 2:3, and total blood to O+ blood is 3:1.
Step-by-step explanation:
To find the ratio of A+ blood to O+ blood in the blood bank, we divide the number of A+ blood by the number of O+ blood. There are 30 A+ blood and 15 O+ blood, so the ratio of A+ blood to O+ blood is 30:15, which can be reduced to 2:1. Therefore, the ratio of A+ blood to O+ blood, reduced to the lowest terms, is 2:1.
To find the ratio of A+ blood to total blood, we add the number of A+ blood and O+ blood and divide the number of A+ blood by the total. There are 30 A+ blood and 15 O+ blood, so the total blood is 30 + 15 = 45. The ratio of A+ blood to total blood is 30:45, which can be reduced to 2:3. Therefore, the ratio of A+ blood to total blood, reduced to the lowest terms, is 2:3.
To find the ratio of total blood to O+ blood, we divide the total number of blood by the number of O+ blood. The total blood is 30 + 15 = 45, and there are 15 O+ blood. The ratio of total blood to O+ blood is 45:15, which can be reduced to 3:1. Therefore, the ratio of total blood to O+ blood, reduced to the lowest terms, is 3:1.