Finding the Third Proportional to 287,416 and 435,099

Step by Step Solution

1. Step 1: Write the proportion equation
   287,416 : 435,099 = 435,099 : x
2. Step 2: Convert to fraction form
   287,416/435,099 = 435,099/x
3. Step 3: Cross multiply
   287,416x = 435,099 × 435,099
4. Step 4: Simplify right side
   287,416x = 189,311,139,801
5. Step 5: Solve for x
   x = 189,311,139,801/287,416
6. Step 6: Final answer
   x = 658,665.97