Finding the Fourth Proportional to 39,839.88, 54,978.55 and 21,934.50

Step by Step Solution

1. Step 1: Write the proportion equation
   39,839.88 : 54,978.55 = 21,934.50 : x
2. Step 2: Convert to fraction form
   39,839.88/54,978.55 = 21,934.50/x
3. Step 3: Cross multiply
   39,839.88x = 54,978.55 × 21,934.50
4. Step 4: Simplify right side
   39,839.88x = 1,205,927,004.98
5. Step 5: Solve for x
   x = 1,205,927,004.98/39,839.88
6. Step 6: Final answer
   x = 30,269.34