Finding the Fourth Proportional to 72.39, 99.99 and 54.06

Step by Step Solution

1. Step 1: Write the proportion equation
   72.39 : 99.99 = 54.06 : x
2. Step 2: Convert to fraction form
   72.39/99.99 = 54.06/x
3. Step 3: Cross multiply
   72.39x = 99.99 × 54.06
4. Step 4: Simplify right side
   72.39x = 5,404.69
5. Step 5: Solve for x
   x = 5,404.69/72.39
6. Step 6: Final answer
   x = 74.67