Answer:
45 cm
Explanation:
First, you want to clarify the ratio:
Khali = 8 cm = 72 cm
____ _____ ______
Juan = 5 cm = x cm
To find the missing variable, cross multiply and simplify for x:
8x = 72(5)
8x = 360
x = 45
So, Juan used 45 cm of ribbon if Khali used 72 cm.