Finding the Fourth Proportional to 31,309.60, 43,223.88 and 21,291.52

Step by Step Solution

1. Step 1: Write the proportion equation
   31,309.60 : 43,223.88 = 21,291.52 : x
2. Step 2: Convert to fraction form
   31,309.60/43,223.88 = 21,291.52/x
3. Step 3: Cross multiply
   31,309.60x = 43,223.88 × 21,291.52
4. Step 4: Simplify right side
   31,309.60x = 920,302,105.50
5. Step 5: Solve for x
   x = 920,302,105.50/31,309.60
6. Step 6: Final answer
   x = 29,393.61