Finding the Third Proportional to 399,345,831,431 and 809,803,927,091.50

Step by Step Solution

1. Step 1: Write the proportion equation
   399,345,831,431 : 809,803,927,091.50 = 809,803,927,091.50 : x
2. Step 2: Convert to fraction form
   399,345,831,431/809,803,927,091.50 = 809,803,927,091.50/x
3. Step 3: Cross multiply
   399,345,831,431x = 809,803,927,091.50 × 809,803,927,091.50
4. Step 4: Simplify right side
   399,345,831,431x = 655,782,400,332,815,455,485,952
5. Step 5: Solve for x
   x = 655,782,400,332,815,455,485,952/399,345,831,431
6. Step 6: Final answer
   x = 1,642,141,594,374.26