Finding the Third Proportional to 258,123.50 and 553,613.50

Step by Step Solution

1. Step 1: Write the proportion equation
   258,123.50 : 553,613.50 = 553,613.50 : x
2. Step 2: Convert to fraction form
   258,123.50/553,613.50 = 553,613.50/x
3. Step 3: Cross multiply
   258,123.50x = 553,613.50 × 553,613.50
4. Step 4: Simplify right side
   258,123.50x = 306,487,907,382.25
5. Step 5: Solve for x
   x = 306,487,907,382.25/258,123.50
6. Step 6: Final answer
   x = 1,187,369.25