Finding the Fourth Proportional to 9,391.31, 12,960.01 and 5,199.56

Step by Step Solution

1. Step 1: Write the proportion equation
   9,391.31 : 12,960.01 = 5,199.56 : x
2. Step 2: Convert to fraction form
   9,391.31/12,960.01 = 5,199.56/x
3. Step 3: Cross multiply
   9,391.31x = 12,960.01 × 5,199.56
4. Step 4: Simplify right side
   9,391.31x = 67,386,388.50
5. Step 5: Solve for x
   x = 67,386,388.50/9,391.31
6. Step 6: Final answer
   x = 7,175.40