There are a total of 63 bikes. if the ratio of blue bikes to black bikes is 4 to 5, how many of the bikes are blue?

The answer is 28 because 4+5=9. 63/9=7. 7 times 4 equals 28.

It said the ratio is 4:5 so that means you have to add 4 and 5

4 + 5 = 9 

so you take 9 and divided by 63 which is 7 then you take 7 and multiply it by 4 and 5

so 28 blue bikes and 35 black bikes

Ithink is a. true, but not sure