Finding the Fourth Proportional to 22,721.31, 31,350.69 and 13,288.05

Step by Step Solution

1. Step 1: Write the proportion equation
   22,721.31 : 31,350.69 = 13,288.05 : x
2. Step 2: Convert to fraction form
   22,721.31/31,350.69 = 13,288.05/x
3. Step 3: Cross multiply
   22,721.31x = 31,350.69 × 13,288.05
4. Step 4: Simplify right side
   22,721.31x = 416,589,536.25
5. Step 5: Solve for x
   x = 416,589,536.25/22,721.31
6. Step 6: Final answer
   x = 18,334.75