Finding the Third Proportional to 78,912,716 and 172,910,872

Step by Step Solution

1. Step 1: Write the proportion equation
   78,912,716 : 172,910,872 = 172,910,872 : x
2. Step 2: Convert to fraction form
   78,912,716/172,910,872 = 172,910,872/x
3. Step 3: Cross multiply
   78,912,716x = 172,910,872 × 172,910,872
4. Step 4: Simplify right side
   78,912,716x = 29,898,169,655,800,384
5. Step 5: Solve for x
   x = 29,898,169,655,800,384/78,912,716
6. Step 6: Final answer
   x = 378,876,449.47