Finding the Fourth Proportional to 13,085.13, 18,057.82 and 7,117.15

Step by Step Solution

1. Step 1: Write the proportion equation
   13,085.13 : 18,057.82 = 7,117.15 : x
2. Step 2: Convert to fraction form
   13,085.13/18,057.82 = 7,117.15/x
3. Step 3: Cross multiply
   13,085.13x = 18,057.82 × 7,117.15
4. Step 4: Simplify right side
   13,085.13x = 128,520,213.61
5. Step 5: Solve for x
   x = 128,520,213.61/13,085.13
6. Step 6: Final answer
   x = 9,821.85