A rectangular prism is 24cm high, 15cm long and 6cm wide. Find the ratio of height to length to width for the prism ...

As the unit of those three are in cm, you can write it in direct form

24 (height) : 15 (length) : 6 (width)

as these three are multiples of 3, they can be divided by 3 to get simplified ratio

Therefore 8:5:2 is the ratio