Finding the Fourth Proportional to 21,180.88, 31,767.14 and 7,139.52

Step by Step Solution

1. Step 1: Write the proportion equation
   21,180.88 : 31,767.14 = 7,139.52 : x
2. Step 2: Convert to fraction form
   21,180.88/31,767.14 = 7,139.52/x
3. Step 3: Cross multiply
   21,180.88x = 31,767.14 × 7,139.52
4. Step 4: Simplify right side
   21,180.88x = 226,802,131.37
5. Step 5: Solve for x
   x = 226,802,131.37/21,180.88
6. Step 6: Final answer
   x = 10,707.87