Finding the Fourth Proportional to 12,928.14, 17,842.49 and 7,891.29

Step by Step Solution

1. Step 1: Write the proportion equation
   12,928.14 : 17,842.49 = 7,891.29 : x
2. Step 2: Convert to fraction form
   12,928.14/17,842.49 = 7,891.29/x
3. Step 3: Cross multiply
   12,928.14x = 17,842.49 × 7,891.29
4. Step 4: Simplify right side
   12,928.14x = 140,800,262.91
5. Step 5: Solve for x
   x = 140,800,262.91/12,928.14
6. Step 6: Final answer
   x = 10,890.99