Finding the Fourth Proportional to 13,145.36, 18,140.72 and 7,177.12

Step by Step Solution

1. Step 1: Write the proportion equation
   13,145.36 : 18,140.72 = 7,177.12 : x
2. Step 2: Convert to fraction form
   13,145.36/18,140.72 = 7,177.12/x
3. Step 3: Cross multiply
   13,145.36x = 18,140.72 × 7,177.12
4. Step 4: Simplify right side
   13,145.36x = 130,198,124.33
5. Step 5: Solve for x
   x = 130,198,124.33/13,145.36
6. Step 6: Final answer
   x = 9,904.49