Finding the Fourth Proportional to 518,529, 715,570.50 and 280,065

Step by Step Solution

1. Step 1: Write the proportion equation
   518,529 : 715,570.50 = 280,065 : x
2. Step 2: Convert to fraction form
   518,529/715,570.50 = 280,065/x
3. Step 3: Cross multiply
   518,529x = 715,570.50 × 280,065
4. Step 4: Simplify right side
   518,529x = 200,406,252,082.50
5. Step 5: Solve for x
   x = 200,406,252,082.50/518,529
6. Step 6: Final answer
   x = 386,489.96