Finding the Fourth Proportional to 13,085.90, 18,058.56 and 7,117.61

Step by Step Solution

1. Step 1: Write the proportion equation
   13,085.90 : 18,058.56 = 7,117.61 : x
2. Step 2: Convert to fraction form
   13,085.90/18,058.56 = 7,117.61/x
3. Step 3: Cross multiply
   13,085.90x = 18,058.56 × 7,117.61
4. Step 4: Simplify right side
   13,085.90x = 128,533,787.24
5. Step 5: Solve for x
   x = 128,533,787.24/13,085.90
6. Step 6: Final answer
   x = 9,822.31