Finding the Third Proportional to 120,108 and 278,020.50

Step by Step Solution

1. Step 1: Write the proportion equation
   120,108 : 278,020.50 = 278,020.50 : x
2. Step 2: Convert to fraction form
   120,108/278,020.50 = 278,020.50/x
3. Step 3: Cross multiply
   120,108x = 278,020.50 × 278,020.50
4. Step 4: Simplify right side
   120,108x = 77,295,398,420.25
5. Step 5: Solve for x
   x = 77,295,398,420.25/120,108
6. Step 6: Final answer
   x = 643,549.13