Finding the Fourth Proportional to 9,118.46, 12,583.56 and 5,139.20

Step by Step Solution

1. Step 1: Write the proportion equation
   9,118.46 : 12,583.56 = 5,139.20 : x
2. Step 2: Convert to fraction form
   9,118.46/12,583.56 = 5,139.20/x
3. Step 3: Cross multiply
   9,118.46x = 12,583.56 × 5,139.20
4. Step 4: Simplify right side
   9,118.46x = 64,669,431.55
5. Step 5: Solve for x
   x = 64,669,431.55/9,118.46
6. Step 6: Final answer
   x = 7,092.14