Finding the Fourth Proportional to 172,499,056.80, 258,620,961.60 and 81,516,357.60

Step by Step Solution

1. Step 1: Write the proportion equation
   172,499,056.80 : 258,620,961.60 = 81,516,357.60 : x
2. Step 2: Convert to fraction form
   172,499,056.80/258,620,961.60 = 81,516,357.60/x
3. Step 3: Cross multiply
   172,499,056.80x = 258,620,961.60 × 81,516,357.60
4. Step 4: Simplify right side
   172,499,056.80x = 21,081,838,788,641,468
5. Step 5: Solve for x
   x = 21,081,838,788,641,468/172,499,056.80
6. Step 6: Final answer
   x = 122,214,226.44