Finding the Fourth Proportional to 12,815.56, 17,681.32 and 7,149.39

Step by Step Solution

1. Step 1: Write the proportion equation
   12,815.56 : 17,681.32 = 7,149.39 : x
2. Step 2: Convert to fraction form
   12,815.56/17,681.32 = 7,149.39/x
3. Step 3: Cross multiply
   12,815.56x = 17,681.32 × 7,149.39
4. Step 4: Simplify right side
   12,815.56x = 126,410,652.39
5. Step 5: Solve for x
   x = 126,410,652.39/12,815.56
6. Step 6: Final answer
   x = 9,863.84