Finding the Fourth Proportional to 215,784.29, 297,817.41 and 129,830.15

Step by Step Solution

1. Step 1: Write the proportion equation
   215,784.29 : 297,817.41 = 129,830.15 : x
2. Step 2: Convert to fraction form
   215,784.29/297,817.41 = 129,830.15/x
3. Step 3: Cross multiply
   215,784.29x = 297,817.41 × 129,830.15
4. Step 4: Simplify right side
   215,784.29x = 38,665,679,012.91
5. Step 5: Solve for x
   x = 38,665,679,012.91/215,784.29
6. Step 6: Final answer
   x = 179,186.72