Finding the Third Proportional to 508,698 and 787,315.50

Step by Step Solution

1. Step 1: Write the proportion equation
   508,698 : 787,315.50 = 787,315.50 : x
2. Step 2: Convert to fraction form
   508,698/787,315.50 = 787,315.50/x
3. Step 3: Cross multiply
   508,698x = 787,315.50 × 787,315.50
4. Step 4: Simplify right side
   508,698x = 619,865,696,540.25
5. Step 5: Solve for x
   x = 619,865,696,540.25/508,698
6. Step 6: Final answer
   x = 1,218,533.78