Finding the Third Proportional to 431,745 and 689,737.50

Step by Step Solution

1. Step 1: Write the proportion equation
   431,745 : 689,737.50 = 689,737.50 : x
2. Step 2: Convert to fraction form
   431,745/689,737.50 = 689,737.50/x
3. Step 3: Cross multiply
   431,745x = 689,737.50 × 689,737.50
4. Step 4: Simplify right side
   431,745x = 475,737,818,906.25
5. Step 5: Solve for x
   x = 475,737,818,906.25/431,745
6. Step 6: Final answer
   x = 1,101,895.38