Finding the Fourth Proportional to 13,156.88, 18,156.20 and 7,188.56

Step by Step Solution

1. Step 1: Write the proportion equation
   13,156.88 : 18,156.20 = 7,188.56 : x
2. Step 2: Convert to fraction form
   13,156.88/18,156.20 = 7,188.56/x
3. Step 3: Cross multiply
   13,156.88x = 18,156.20 × 7,188.56
4. Step 4: Simplify right side
   13,156.88x = 130,516,933.07
5. Step 5: Solve for x
   x = 130,516,933.07/13,156.88
6. Step 6: Final answer
   x = 9,920.05