Finding the Fourth Proportional to 40,815.72, 61,229.42 and 12,738.29

Step by Step Solution

1. Step 1: Write the proportion equation
   40,815.72 : 61,229.42 = 12,738.29 : x
2. Step 2: Convert to fraction form
   40,815.72/61,229.42 = 12,738.29/x
3. Step 3: Cross multiply
   40,815.72x = 61,229.42 × 12,738.29
4. Step 4: Simplify right side
   40,815.72x = 779,958,108.49
5. Step 5: Solve for x
   x = 779,958,108.49/40,815.72
6. Step 6: Final answer
   x = 19,109.26