Finding the Fourth Proportional to 499,922.29, 689,875.61 and 285,131.55

Step by Step Solution

1. Step 1: Write the proportion equation
   499,922.29 : 689,875.61 = 285,131.55 : x
2. Step 2: Convert to fraction form
   499,922.29/689,875.61 = 285,131.55/x
3. Step 3: Cross multiply
   499,922.29x = 689,875.61 × 285,131.55
4. Step 4: Simplify right side
   499,922.29x = 196,705,301,986.50
5. Step 5: Solve for x
   x = 196,705,301,986.50/499,922.29
6. Step 6: Final answer
   x = 393,471.76