Question

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?

a) 28
b) 35
c) 40

Answer 1

To determine the number of blue bikes, we can set up a ratio equation and solve for the unknown variable. The correct answer is 28 (a).

Step-by-step explanation:

To find out how many of the bikes are blue, we need to determine the number of blue bikes based on the given ratio.

Let's say the total number of blue bikes is '4x' and the total number of black bikes is '5x'.

According to the given information, the sum of blue bikes and black bikes is 63. So, we have the equation: 4x + 5x = 63.

Simplifying the equation, we get: 9x = 63.

Dividing both sides by 9, we find that x = 7. Therefore, the number of blue bikes is 4x = 4 * 7 = 28.

So, the correct answer is 28 (a).