Finding the Third Proportional to 148,689 and 309,685.50

Step by Step Solution

1. Step 1: Write the proportion equation
   148,689 : 309,685.50 = 309,685.50 : x
2. Step 2: Convert to fraction form
   148,689/309,685.50 = 309,685.50/x
3. Step 3: Cross multiply
   148,689x = 309,685.50 × 309,685.50
4. Step 4: Simplify right side
   148,689x = 95,905,108,910.25
5. Step 5: Solve for x
   x = 95,905,108,910.25/148,689
6. Step 6: Final answer
   x = 645,004.73