Finding the Fourth Proportional to 429,491.10, 644,309.55 and 129,969.30

Step by Step Solution

1. Step 1: Write the proportion equation
   429,491.10 : 644,309.55 = 129,969.30 : x
2. Step 2: Convert to fraction form
   429,491.10/644,309.55 = 129,969.30/x
3. Step 3: Cross multiply
   429,491.10x = 644,309.55 × 129,969.30
4. Step 4: Simplify right side
   429,491.10x = 83,740,461,196.82
5. Step 5: Solve for x
   x = 83,740,461,196.82/429,491.10
6. Step 6: Final answer
   x = 194,976.01