Finding the Fourth Proportional to 20,930.27, 31,390.55 and 7,788.83

Step by Step Solution

1. Step 1: Write the proportion equation
   20,930.27 : 31,390.55 = 7,788.83 : x
2. Step 2: Convert to fraction form
   20,930.27/31,390.55 = 7,788.83/x
3. Step 3: Cross multiply
   20,930.27x = 31,390.55 × 7,788.83
4. Step 4: Simplify right side
   20,930.27x = 244,495,618.61
5. Step 5: Solve for x
   x = 244,495,618.61/20,930.27
6. Step 6: Final answer
   x = 11,681.44