Finding the Fourth Proportional to 39,884.86, 55,038.50 and 21,979.86

Step by Step Solution

1. Step 1: Write the proportion equation
   39,884.86 : 55,038.50 = 21,979.86 : x
2. Step 2: Convert to fraction form
   39,884.86/55,038.50 = 21,979.86/x
3. Step 3: Cross multiply
   39,884.86x = 55,038.50 × 21,979.86
4. Step 4: Simplify right side
   39,884.86x = 1,209,738,524.61
5. Step 5: Solve for x
   x = 1,209,738,524.61/39,884.86
6. Step 6: Final answer
   x = 30,330.77