Finding the Fourth Proportional to 87,978.78, 131,968.26 and 21,418.38

Step by Step Solution

1. Step 1: Write the proportion equation
   87,978.78 : 131,968.26 = 21,418.38 : x
2. Step 2: Convert to fraction form
   87,978.78/131,968.26 = 21,418.38/x
3. Step 3: Cross multiply
   87,978.78x = 131,968.26 × 21,418.38
4. Step 4: Simplify right side
   87,978.78x = 2,826,546,340.62
5. Step 5: Solve for x
   x = 2,826,546,340.62/87,978.78
6. Step 6: Final answer
   x = 32,127.59