Finding the Fourth Proportional to 12,891.38, 17,793.33 and 7,920.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,891.38 : 17,793.33 = 7,920.50 : x
2. Step 2: Convert to fraction form
   12,891.38/17,793.33 = 7,920.50/x
3. Step 3: Cross multiply
   12,891.38x = 17,793.33 × 7,920.50
4. Step 4: Simplify right side
   12,891.38x = 140,932,070.27
5. Step 5: Solve for x
   x = 140,932,070.27/12,891.38
6. Step 6: Final answer
   x = 10,932.27