Finding the Fourth Proportional to 31,419.20, 47,123.91 and 20,403.98

Step by Step Solution

1. Step 1: Write the proportion equation
   31,419.20 : 47,123.91 = 20,403.98 : x
2. Step 2: Convert to fraction form
   31,419.20/47,123.91 = 20,403.98/x
3. Step 3: Cross multiply
   31,419.20x = 47,123.91 × 20,403.98
4. Step 4: Simplify right side
   31,419.20x = 961,515,317.16
5. Step 5: Solve for x
   x = 961,515,317.16/31,419.20
6. Step 6: Final answer
   x = 30,602.79