Finding the Fourth Proportional to 402,667.85, 555,681.98 and 221,382.86

Step by Step Solution

1. Step 1: Write the proportion equation
   402,667.85 : 555,681.98 = 221,382.86 : x
2. Step 2: Convert to fraction form
   402,667.85/555,681.98 = 221,382.86/x
3. Step 3: Cross multiply
   402,667.85x = 555,681.98 × 221,382.86
4. Step 4: Simplify right side
   402,667.85x = 123,018,464,875.95
5. Step 5: Solve for x
   x = 123,018,464,875.95/402,667.85
6. Step 6: Final answer
   x = 305,508.53