Finding the Third Proportional to 438,870 and 655,434

Step by Step Solution

1. Step 1: Write the proportion equation
   438,870 : 655,434 = 655,434 : x
2. Step 2: Convert to fraction form
   438,870/655,434 = 655,434/x
3. Step 3: Cross multiply
   438,870x = 655,434 × 655,434
4. Step 4: Simplify right side
   438,870x = 429,593,728,356
5. Step 5: Solve for x
   x = 429,593,728,356/438,870
6. Step 6: Final answer
   x = 978,863.28