Finding the Fourth Proportional to 21,189.56, 31,788.90 and 7,149.94

Step by Step Solution

1. Step 1: Write the proportion equation
   21,189.56 : 31,788.90 = 7,149.94 : x
2. Step 2: Convert to fraction form
   21,189.56/31,788.90 = 7,149.94/x
3. Step 3: Cross multiply
   21,189.56x = 31,788.90 × 7,149.94
4. Step 4: Simplify right side
   21,189.56x = 227,288,648.19
5. Step 5: Solve for x
   x = 227,288,648.19/21,189.56
6. Step 6: Final answer
   x = 10,726.44