Finding the Fourth Proportional to 12,578.37, 18,876.69 and 10,142.61

Step by Step Solution

1. Step 1: Write the proportion equation
   12,578.37 : 18,876.69 = 10,142.61 : x
2. Step 2: Convert to fraction form
   12,578.37/18,876.69 = 10,142.61/x
3. Step 3: Cross multiply
   12,578.37x = 18,876.69 × 10,142.61
4. Step 4: Simplify right side
   12,578.37x = 191,458,904.76
5. Step 5: Solve for x
   x = 191,458,904.76/12,578.37
6. Step 6: Final answer
   x = 15,221.28