Finding the Third Proportional to 284,404 and 428,406

Step by Step Solution

1. Step 1: Write the proportion equation
   284,404 : 428,406 = 428,406 : x
2. Step 2: Convert to fraction form
   284,404/428,406 = 428,406/x
3. Step 3: Cross multiply
   284,404x = 428,406 × 428,406
4. Step 4: Simplify right side
   284,404x = 183,531,700,836
5. Step 5: Solve for x
   x = 183,531,700,836/284,404
6. Step 6: Final answer
   x = 645,320.39