Step-by-step explanation:
GIVEN: O is the mid point of AC & BD.
Therefore, AO = CO & BO = DO

The number is 75
15*3=75
75<100
7+5=12
75 is odd
Since all of the numbers share a common number that divides them, a simplified 4:22:30 ratio would be 2:11:15, as it would not be able to divide them further with the same number and still get whole numbers, or 1: 5.5: 7.5, if you wish to split them further to 1.