Finding the Fourth Proportional to 13,144.16, 18,139.14 and 7,479.20

Step by Step Solution

1. Step 1: Write the proportion equation
   13,144.16 : 18,139.14 = 7,479.20 : x
2. Step 2: Convert to fraction form
   13,144.16/18,139.14 = 7,479.20/x
3. Step 3: Cross multiply
   13,144.16x = 18,139.14 × 7,479.20
4. Step 4: Simplify right side
   13,144.16x = 135,666,255.89
5. Step 5: Solve for x
   x = 135,666,255.89/13,144.16
6. Step 6: Final answer
   x = 10,321.41