Finding the Fourth Proportional to 12,891.69, 17,792.15 and 7,857.49

Step by Step Solution

1. Step 1: Write the proportion equation
   12,891.69 : 17,792.15 = 7,857.49 : x
2. Step 2: Convert to fraction form
   12,891.69/17,792.15 = 7,857.49/x
3. Step 3: Cross multiply
   12,891.69x = 17,792.15 × 7,857.49
4. Step 4: Simplify right side
   12,891.69x = 139,801,697.32
5. Step 5: Solve for x
   x = 139,801,697.32/12,891.69
6. Step 6: Final answer
   x = 10,844.33