Finding the Fourth Proportional to 13,139.01, 18,257.81 and 13,004.15

Step by Step Solution

1. Step 1: Write the proportion equation
   13,139.01 : 18,257.81 = 13,004.15 : x
2. Step 2: Convert to fraction form
   13,139.01/18,257.81 = 13,004.15/x
3. Step 3: Cross multiply
   13,139.01x = 18,257.81 × 13,004.15
4. Step 4: Simplify right side
   13,139.01x = 237,427,143.60
5. Step 5: Solve for x
   x = 237,427,143.60/13,139.01
6. Step 6: Final answer
   x = 18,070.40