Finding the Third Proportional to 399,436 and 868,856

Step by Step Solution

1. Step 1: Write the proportion equation
   399,436 : 868,856 = 868,856 : x
2. Step 2: Convert to fraction form
   399,436/868,856 = 868,856/x
3. Step 3: Cross multiply
   399,436x = 868,856 × 868,856
4. Step 4: Simplify right side
   399,436x = 754,910,748,736
5. Step 5: Solve for x
   x = 754,910,748,736/399,436
6. Step 6: Final answer
   x = 1,889,941.69