Finding the Fourth Proportional to 172,438.56, 258,312.24 and 78,815.52

Step by Step Solution

1. Step 1: Write the proportion equation
   172,438.56 : 258,312.24 = 78,815.52 : x
2. Step 2: Convert to fraction form
   172,438.56/258,312.24 = 78,815.52/x
3. Step 3: Cross multiply
   172,438.56x = 258,312.24 × 78,815.52
4. Step 4: Simplify right side
   172,438.56x = 20,359,013,517.96
5. Step 5: Solve for x
   x = 20,359,013,517.96/172,438.56
6. Step 6: Final answer
   x = 118,065.32