Finding the Fourth Proportional to 288,795.31, 433,221.89 and 99,230.70

Step by Step Solution

1. Step 1: Write the proportion equation
   288,795.31 : 433,221.89 = 99,230.70 : x
2. Step 2: Convert to fraction form
   288,795.31/433,221.89 = 99,230.70/x
3. Step 3: Cross multiply
   288,795.31x = 433,221.89 × 99,230.70
4. Step 4: Simplify right side
   288,795.31x = 42,988,911,648.10
5. Step 5: Solve for x
   x = 42,988,911,648.10/288,795.31
6. Step 6: Final answer
   x = 148,855.99