Finding the Fourth Proportional to 9,375.21, 12,911.54 and 9,171.09

Step by Step Solution

1. Step 1: Write the proportion equation
   9,375.21 : 12,911.54 = 9,171.09 : x
2. Step 2: Convert to fraction form
   9,375.21/12,911.54 = 9,171.09/x
3. Step 3: Cross multiply
   9,375.21x = 12,911.54 × 9,171.09
4. Step 4: Simplify right side
   9,375.21x = 118,412,849.52
5. Step 5: Solve for x
   x = 118,412,849.52/9,375.21
6. Step 6: Final answer
   x = 12,630.42