Okon and Akpan are to share some oranges in the ratio 4:5 .Okon gets 12 oranges . How many oranges does Akpan get?
Let's determine the total number of parts in the ratio by summing the ratio values: 4 + 5 = 9 parts.
Since 12 represents 4 parts of the ratio, we need to find out how many parts each unit represents: 12/4 = <<12/4=3>>3 parts per unit.
Finally, to find the number of oranges Akpan gets, we multiply the number of units he has by the parts per unit: 5 units * 3 parts per unit = <<5*3=15>>15 oranges. Answer: \boxed{15}.