Finding the Fourth Proportional to 402,477.86, 555,392.55 and 221,185.89

Step by Step Solution

1. Step 1: Write the proportion equation
   402,477.86 : 555,392.55 = 221,185.89 : x
2. Step 2: Convert to fraction form
   402,477.86/555,392.55 = 221,185.89/x
3. Step 3: Cross multiply
   402,477.86x = 555,392.55 × 221,185.89
4. Step 4: Simplify right side
   402,477.86x = 122,844,995,056.40
5. Step 5: Solve for x
   x = 122,844,995,056.40/402,477.86
6. Step 6: Final answer
   x = 305,221.74