Finding the Fourth Proportional to 398,091.82, 549,362.88 and 216,806.78

Step by Step Solution

1. Step 1: Write the proportion equation
   398,091.82 : 549,362.88 = 216,806.78 : x
2. Step 2: Convert to fraction form
   398,091.82/549,362.88 = 216,806.78/x
3. Step 3: Cross multiply
   398,091.82x = 549,362.88 × 216,806.78
4. Step 4: Simplify right side
   398,091.82x = 119,105,597,064.33
5. Step 5: Solve for x
   x = 119,105,597,064.33/398,091.82
6. Step 6: Final answer
   x = 299,191.27