Finding the Fourth Proportional to 72,129.43, 99,536.79 and 40,298.56

Step by Step Solution

1. Step 1: Write the proportion equation
   72,129.43 : 99,536.79 = 40,298.56 : x
2. Step 2: Convert to fraction form
   72,129.43/99,536.79 = 40,298.56/x
3. Step 3: Cross multiply
   72,129.43x = 99,536.79 × 40,298.56
4. Step 4: Simplify right side
   72,129.43x = 4,011,189,304.02
5. Step 5: Solve for x
   x = 4,011,189,304.02/72,129.43
6. Step 6: Final answer
   x = 55,610.99