Finding the Fourth Proportional to 13,156.55, 18,155.49 and 7,188.42

Step by Step Solution

1. Step 1: Write the proportion equation
   13,156.55 : 18,155.49 = 7,188.42 : x
2. Step 2: Convert to fraction form
   13,156.55/18,155.49 = 7,188.42/x
3. Step 3: Cross multiply
   13,156.55x = 18,155.49 × 7,188.42
4. Step 4: Simplify right side
   13,156.55x = 130,509,287.43
5. Step 5: Solve for x
   x = 130,509,287.43/13,156.55
6. Step 6: Final answer
   x = 9,919.72