Finding the Fourth Proportional to 31,031.64, 42,793.88 and 20,845.71

Step by Step Solution

1. Step 1: Write the proportion equation
   31,031.64 : 42,793.88 = 20,845.71 : x
2. Step 2: Convert to fraction form
   31,031.64/42,793.88 = 20,845.71/x
3. Step 3: Cross multiply
   31,031.64x = 42,793.88 × 20,845.71
4. Step 4: Simplify right side
   31,031.64x = 892,068,708.03
5. Step 5: Solve for x
   x = 892,068,708.03/31,031.64
6. Step 6: Final answer
   x = 28,747.07