Finding the Third Proportional to 289,820 and 443,375

Step by Step Solution

1. Step 1: Write the proportion equation
   289,820 : 443,375 = 443,375 : x
2. Step 2: Convert to fraction form
   289,820/443,375 = 443,375/x
3. Step 3: Cross multiply
   289,820x = 443,375 × 443,375
4. Step 4: Simplify right side
   289,820x = 196,581,390,625
5. Step 5: Solve for x
   x = 196,581,390,625/289,820
6. Step 6: Final answer
   x = 678,287.87