Finding the Third Proportional to 387,139.50 and 840,766.50

Step by Step Solution

1. Step 1: Write the proportion equation
   387,139.50 : 840,766.50 = 840,766.50 : x
2. Step 2: Convert to fraction form
   387,139.50/840,766.50 = 840,766.50/x
3. Step 3: Cross multiply
   387,139.50x = 840,766.50 × 840,766.50
4. Step 4: Simplify right side
   387,139.50x = 706,888,307,522.25
5. Step 5: Solve for x
   x = 706,888,307,522.25/387,139.50
6. Step 6: Final answer
   x = 1,825,926.59