Finding the Fourth Proportional to 216,978.18, 325,519.25 and 90,548.09

Step by Step Solution

1. Step 1: Write the proportion equation
   216,978.18 : 325,519.25 = 90,548.09 : x
2. Step 2: Convert to fraction form
   216,978.18/325,519.25 = 90,548.09/x
3. Step 3: Cross multiply
   216,978.18x = 325,519.25 × 90,548.09
4. Step 4: Simplify right side
   216,978.18x = 29,475,144,265.40
5. Step 5: Solve for x
   x = 29,475,144,265.40/216,978.18
6. Step 6: Final answer
   x = 135,843.82