Finding the Third Proportional to 265,369 and 390,223.50

Step by Step Solution

1. Step 1: Write the proportion equation
   265,369 : 390,223.50 = 390,223.50 : x
2. Step 2: Convert to fraction form
   265,369/390,223.50 = 390,223.50/x
3. Step 3: Cross multiply
   265,369x = 390,223.50 × 390,223.50
4. Step 4: Simplify right side
   265,369x = 152,274,379,952.25
5. Step 5: Solve for x
   x = 152,274,379,952.25/265,369
6. Step 6: Final answer
   x = 573,821.28