Finding the Fourth Proportional to 13,144.45, 18,139.10 and 7,479.07

Step by Step Solution

1. Step 1: Write the proportion equation
   13,144.45 : 18,139.10 = 7,479.07 : x
2. Step 2: Convert to fraction form
   13,144.45/18,139.10 = 7,479.07/x
3. Step 3: Cross multiply
   13,144.45x = 18,139.10 × 7,479.07
4. Step 4: Simplify right side
   13,144.45x = 135,663,515.89
5. Step 5: Solve for x
   x = 135,663,515.89/13,144.45
6. Step 6: Final answer
   x = 10,320.98