Finding the Fourth Proportional to 72,346.56, 99,938.88 and 54,578.40

Step by Step Solution

1. Step 1: Write the proportion equation
   72,346.56 : 99,938.88 = 54,578.40 : x
2. Step 2: Convert to fraction form
   72,346.56/99,938.88 = 54,578.40/x
3. Step 3: Cross multiply
   72,346.56x = 99,938.88 × 54,578.40
4. Step 4: Simplify right side
   72,346.56x = 5,454,504,168.19
5. Step 5: Solve for x
   x = 5,454,504,168.19/72,346.56
6. Step 6: Final answer
   x = 75,394.11