Finding the Third Proportional to 120,456 and 259,411.50

Step by Step Solution

1. Step 1: Write the proportion equation
   120,456 : 259,411.50 = 259,411.50 : x
2. Step 2: Convert to fraction form
   120,456/259,411.50 = 259,411.50/x
3. Step 3: Cross multiply
   120,456x = 259,411.50 × 259,411.50
4. Step 4: Simplify right side
   120,456x = 67,294,326,332.25
5. Step 5: Solve for x
   x = 67,294,326,332.25/120,456
6. Step 6: Final answer
   x = 558,663.13