Finding the Fourth Proportional to 172,499,605.80, 258,621,785.10 and 81,516,906.60

Step by Step Solution

1. Step 1: Write the proportion equation
   172,499,605.80 : 258,621,785.10 = 81,516,906.60 : x
2. Step 2: Convert to fraction form
   172,499,605.80/258,621,785.10 = 81,516,906.60/x
3. Step 3: Cross multiply
   172,499,605.80x = 258,621,785.10 × 81,516,906.60
4. Step 4: Simplify right side
   172,499,605.80x = 21,082,047,900,721,968
5. Step 5: Solve for x
   x = 21,082,047,900,721,968/172,499,605.80
6. Step 6: Final answer
   x = 122,215,049.73