Finding the Fourth Proportional to 9,158.56, 12,638.09 and 5,381.87

Step by Step Solution

1. Step 1: Write the proportion equation
   9,158.56 : 12,638.09 = 5,381.87 : x
2. Step 2: Convert to fraction form
   9,158.56/12,638.09 = 5,381.87/x
3. Step 3: Cross multiply
   9,158.56x = 12,638.09 × 5,381.87
4. Step 4: Simplify right side
   9,158.56x = 68,016,507.69
5. Step 5: Solve for x
   x = 68,016,507.69/9,158.56
6. Step 6: Final answer
   x = 7,426.55