Finding the Fourth Proportional to 30,660.01, 42,294.91 and 20,591.31

Step by Step Solution

1. Step 1: Write the proportion equation
   30,660.01 : 42,294.91 = 20,591.31 : x
2. Step 2: Convert to fraction form
   30,660.01/42,294.91 = 20,591.31/x
3. Step 3: Cross multiply
   30,660.01x = 42,294.91 × 20,591.31
4. Step 4: Simplify right side
   30,660.01x = 870,907,603.23
5. Step 5: Solve for x
   x = 870,907,603.23/30,660.01
6. Step 6: Final answer
   x = 28,405.33