Finding the Third Proportional to 120,667.50 and 257,359.50

Step by Step Solution

1. Step 1: Write the proportion equation
   120,667.50 : 257,359.50 = 257,359.50 : x
2. Step 2: Convert to fraction form
   120,667.50/257,359.50 = 257,359.50/x
3. Step 3: Cross multiply
   120,667.50x = 257,359.50 × 257,359.50
4. Step 4: Simplify right side
   120,667.50x = 66,233,912,240.25
5. Step 5: Solve for x
   x = 66,233,912,240.25/120,667.50
6. Step 6: Final answer
   x = 548,896.03