Finding the Third Proportional to 308,500 and 641,624

Step by Step Solution

1. Step 1: Write the proportion equation
   308,500 : 641,624 = 641,624 : x
2. Step 2: Convert to fraction form
   308,500/641,624 = 641,624/x
3. Step 3: Cross multiply
   308,500x = 641,624 × 641,624
4. Step 4: Simplify right side
   308,500x = 411,681,357,376
5. Step 5: Solve for x
   x = 411,681,357,376/308,500
6. Step 6: Final answer
   x = 1,334,461.45