Finding the Fourth Proportional to 9,165.53, 12,648.42 and 5,186.55

Step by Step Solution

1. Step 1: Write the proportion equation
   9,165.53 : 12,648.42 = 5,186.55 : x
2. Step 2: Convert to fraction form
   9,165.53/12,648.42 = 5,186.55/x
3. Step 3: Cross multiply
   9,165.53x = 12,648.42 × 5,186.55
4. Step 4: Simplify right side
   9,165.53x = 65,601,662.75
5. Step 5: Solve for x
   x = 65,601,662.75/9,165.53
6. Step 6: Final answer
   x = 7,157.44