Finding the Fourth Proportional to 23,131.52, 31,921.32 and 12,521.28

Step by Step Solution

1. Step 1: Write the proportion equation
   23,131.52 : 31,921.32 = 12,521.28 : x
2. Step 2: Convert to fraction form
   23,131.52/31,921.32 = 12,521.28/x
3. Step 3: Cross multiply
   23,131.52x = 31,921.32 × 12,521.28
4. Step 4: Simplify right side
   23,131.52x = 399,695,785.69
5. Step 5: Solve for x
   x = 399,695,785.69/23,131.52
6. Step 6: Final answer
   x = 17,279.27