Finding the Third Proportional to 309,091,104 and 643,563,072

Step by Step Solution

1. Step 1: Write the proportion equation
   309,091,104 : 643,563,072 = 643,563,072 : x
2. Step 2: Convert to fraction form
   309,091,104/643,563,072 = 643,563,072/x
3. Step 3: Cross multiply
   309,091,104x = 643,563,072 × 643,563,072
4. Step 4: Simplify right side
   309,091,104x = 414,173,427,642,077,184
5. Step 5: Solve for x
   x = 414,173,427,642,077,184/309,091,104
6. Step 6: Final answer
   x = 1,339,972,009.17