Finding the Fourth Proportional to 12,817, 17,686.57 and 7,439.59

Step by Step Solution

1. Step 1: Write the proportion equation
   12,817 : 17,686.57 = 7,439.59 : x
2. Step 2: Convert to fraction form
   12,817/17,686.57 = 7,439.59/x
3. Step 3: Cross multiply
   12,817x = 17,686.57 × 7,439.59
4. Step 4: Simplify right side
   12,817x = 131,580,829.31
5. Step 5: Solve for x
   x = 131,580,829.31/12,817
6. Step 6: Final answer
   x = 10,266.12