Finding the Third Proportional to 90,603 and 139,864.50

Step by Step Solution

1. Step 1: Write the proportion equation
   90,603 : 139,864.50 = 139,864.50 : x
2. Step 2: Convert to fraction form
   90,603/139,864.50 = 139,864.50/x
3. Step 3: Cross multiply
   90,603x = 139,864.50 × 139,864.50
4. Step 4: Simplify right side
   90,603x = 19,562,078,360.25
5. Step 5: Solve for x
   x = 19,562,078,360.25/90,603
6. Step 6: Final answer
   x = 215,909.83