Finding the Fourth Proportional to 172,499,088.80, 258,621,009.60 and 81,516,389.60

Step by Step Solution

1. Step 1: Write the proportion equation
   172,499,088.80 : 258,621,009.60 = 81,516,389.60 : x
2. Step 2: Convert to fraction form
   172,499,088.80/258,621,009.60 = 81,516,389.60/x
3. Step 3: Cross multiply
   172,499,088.80x = 258,621,009.60 × 81,516,389.60
4. Step 4: Simplify right side
   172,499,088.80x = 21,081,850,977,298,940
5. Step 5: Solve for x
   x = 21,081,850,977,298,940/172,499,088.80
6. Step 6: Final answer
   x = 122,214,274.43