Finding the Fourth Proportional to 31,456.32, 47,200.72 and 13,938.56

Step by Step Solution

1. Step 1: Write the proportion equation
   31,456.32 : 47,200.72 = 13,938.56 : x
2. Step 2: Convert to fraction form
   31,456.32/47,200.72 = 13,938.56/x
3. Step 3: Cross multiply
   31,456.32x = 47,200.72 × 13,938.56
4. Step 4: Simplify right side
   31,456.32x = 657,910,067.76
5. Step 5: Solve for x
   x = 657,910,067.76/31,456.32
6. Step 6: Final answer
   x = 20,915.04