Finding the Third Proportional to 289,710 and 443,205

Step by Step Solution

1. Step 1: Write the proportion equation
   289,710 : 443,205 = 443,205 : x
2. Step 2: Convert to fraction form
   289,710/443,205 = 443,205/x
3. Step 3: Cross multiply
   289,710x = 443,205 × 443,205
4. Step 4: Simplify right side
   289,710x = 196,430,672,025
5. Step 5: Solve for x
   x = 196,430,672,025/289,710
6. Step 6: Final answer
   x = 678,025.17