Finding the Fourth Proportional to 13,105.55, 18,085.02 and 7,137.20

Step by Step Solution

1. Step 1: Write the proportion equation
   13,105.55 : 18,085.02 = 7,137.20 : x
2. Step 2: Convert to fraction form
   13,105.55/18,085.02 = 7,137.20/x
3. Step 3: Cross multiply
   13,105.55x = 18,085.02 × 7,137.20
4. Step 4: Simplify right side
   13,105.55x = 129,076,314.32
5. Step 5: Solve for x
   x = 129,076,314.32/13,105.55
6. Step 6: Final answer
   x = 9,848.98