Finding the Fourth Proportional to 13,139.17, 18,132.17 and 7,170.89

Step by Step Solution

1. Step 1: Write the proportion equation
   13,139.17 : 18,132.17 = 7,170.89 : x
2. Step 2: Convert to fraction form
   13,139.17/18,132.17 = 7,170.89/x
3. Step 3: Cross multiply
   13,139.17x = 18,132.17 × 7,170.89
4. Step 4: Simplify right side
   13,139.17x = 130,023,670.02
5. Step 5: Solve for x
   x = 130,023,670.02/13,139.17
6. Step 6: Final answer
   x = 9,895.88