Finding the Fourth Proportional to 72,188.28, 99,620.10 and 40,359.24

Step by Step Solution

1. Step 1: Write the proportion equation
   72,188.28 : 99,620.10 = 40,359.24 : x
2. Step 2: Convert to fraction form
   72,188.28/99,620.10 = 40,359.24/x
3. Step 3: Cross multiply
   72,188.28x = 99,620.10 × 40,359.24
4. Step 4: Simplify right side
   72,188.28x = 4,020,591,524.72
5. Step 5: Solve for x
   x = 4,020,591,524.72/72,188.28
6. Step 6: Final answer
   x = 55,695.90