Finding the Third Proportional to 509,787,117 and 787,200,499

Step by Step Solution

1. Step 1: Write the proportion equation
   509,787,117 : 787,200,499 = 787,200,499 : x
2. Step 2: Convert to fraction form
   509,787,117/787,200,499 = 787,200,499/x
3. Step 3: Cross multiply
   509,787,117x = 787,200,499 × 787,200,499
4. Step 4: Simplify right side
   509,787,117x = 619,684,625,625,848,960
5. Step 5: Solve for x
   x = 619,684,625,625,848,960/509,787,117
6. Step 6: Final answer
   x = 1,215,575,295.96