Finding the Fourth Proportional to 398,667.83, 550,141.37 and 217,378.28

Step by Step Solution

1. Step 1: Write the proportion equation
   398,667.83 : 550,141.37 = 217,378.28 : x
2. Step 2: Convert to fraction form
   398,667.83/550,141.37 = 217,378.28/x
3. Step 3: Cross multiply
   398,667.83x = 550,141.37 × 217,378.28
4. Step 4: Simplify right side
   398,667.83x = 119,588,785,871.07
5. Step 5: Solve for x
   x = 119,588,785,871.07/398,667.83
6. Step 6: Final answer
   x = 299,971.00