Finding the Third Proportional to 209,665.50 and 279,337.50

Step by Step Solution

1. Step 1: Write the proportion equation
   209,665.50 : 279,337.50 = 279,337.50 : x
2. Step 2: Convert to fraction form
   209,665.50/279,337.50 = 279,337.50/x
3. Step 3: Cross multiply
   209,665.50x = 279,337.50 × 279,337.50
4. Step 4: Simplify right side
   209,665.50x = 78,029,438,906.25
5. Step 5: Solve for x
   x = 78,029,438,906.25/209,665.50
6. Step 6: Final answer
   x = 372,161.56