Finding the Fourth Proportional to 13,140.94, 18,134.56 and 7,172.76

Step by Step Solution

1. Step 1: Write the proportion equation
   13,140.94 : 18,134.56 = 7,172.76 : x
2. Step 2: Convert to fraction form
   13,140.94/18,134.56 = 7,172.76/x
3. Step 3: Cross multiply
   13,140.94x = 18,134.56 × 7,172.76
4. Step 4: Simplify right side
   13,140.94x = 130,074,846.59
5. Step 5: Solve for x
   x = 130,074,846.59/13,140.94
6. Step 6: Final answer
   x = 9,898.44