Finding the Fourth Proportional to 31,108.88, 42,945.57 and 21,556.01

Step by Step Solution

1. Step 1: Write the proportion equation
   31,108.88 : 42,945.57 = 21,556.01 : x
2. Step 2: Convert to fraction form
   31,108.88/42,945.57 = 21,556.01/x
3. Step 3: Cross multiply
   31,108.88x = 42,945.57 × 21,556.01
4. Step 4: Simplify right side
   31,108.88x = 925,734,921.65
5. Step 5: Solve for x
   x = 925,734,921.65/31,108.88
6. Step 6: Final answer
   x = 29,757.90