Finding the Fourth Proportional to 13,928.78, 20,887.29 and 5,920.31

Step by Step Solution

1. Step 1: Write the proportion equation
   13,928.78 : 20,887.29 = 5,920.31 : x
2. Step 2: Convert to fraction form
   13,928.78/20,887.29 = 5,920.31/x
3. Step 3: Cross multiply
   13,928.78x = 20,887.29 × 5,920.31
4. Step 4: Simplify right side
   13,928.78x = 123,659,127.42
5. Step 5: Solve for x
   x = 123,659,127.42/13,928.78
6. Step 6: Final answer
   x = 8,877.96