Finding the Fourth Proportional to 72.51, 108.89 and 54.24

Step by Step Solution

1. Step 1: Write the proportion equation
   72.51 : 108.89 = 54.24 : x
2. Step 2: Convert to fraction form
   72.51/108.89 = 54.24/x
3. Step 3: Cross multiply
   72.51x = 108.89 × 54.24
4. Step 4: Simplify right side
   72.51x = 5,906.02
5. Step 5: Solve for x
   x = 5,906.02/72.51
6. Step 6: Final answer
   x = 81.45