Finding the Fourth Proportional to 9,171.43, 12,607.85 and 7,890.60

Step by Step Solution

1. Step 1: Write the proportion equation
   9,171.43 : 12,607.85 = 7,890.60 : x
2. Step 2: Convert to fraction form
   9,171.43/12,607.85 = 7,890.60/x
3. Step 3: Cross multiply
   9,171.43x = 12,607.85 × 7,890.60
4. Step 4: Simplify right side
   9,171.43x = 99,483,523.83
5. Step 5: Solve for x
   x = 99,483,523.83/9,171.43
6. Step 6: Final answer
   x = 10,847.11