Answer :
Answer:
28 bikes are blue
Step-by-step explanation:
Set up the ratio:
Blue : Black
4 : 5
Find the total # of bikes in the ratio:
4 + 5 = 9
Find the relationship between 63 and 9:
63/9 = 7
Multiply both sides of the ratio by 7:
4(7) = 28
5(7) = 35
28 : 35
Therefore, the number of blue bikes is 28.