Finding the Fourth Proportional to 72,201.28, 99,642.72 and 40,369.60

Step by Step Solution

1. Step 1: Write the proportion equation
   72,201.28 : 99,642.72 = 40,369.60 : x
2. Step 2: Convert to fraction form
   72,201.28/99,642.72 = 40,369.60/x
3. Step 3: Cross multiply
   72,201.28x = 99,642.72 × 40,369.60
4. Step 4: Simplify right side
   72,201.28x = 4,022,536,749.31
5. Step 5: Solve for x
   x = 4,022,536,749.31/72,201.28
6. Step 6: Final answer
   x = 55,712.82