Finding the Fourth Proportional to 129,006, 178,028.72 and 71,645.47

Step by Step Solution

1. Step 1: Write the proportion equation
   129,006 : 178,028.72 = 71,645.47 : x
2. Step 2: Convert to fraction form
   129,006/178,028.72 = 71,645.47/x
3. Step 3: Cross multiply
   129,006x = 178,028.72 × 71,645.47
4. Step 4: Simplify right side
   129,006x = 12,754,951,317.90
5. Step 5: Solve for x
   x = 12,754,951,317.90/129,006
6. Step 6: Final answer
   x = 98,870.99