Finding the Fourth Proportional to 9,118.72, 12,584.08 and 5,139.96

Step by Step Solution

1. Step 1: Write the proportion equation
   9,118.72 : 12,584.08 = 5,139.96 : x
2. Step 2: Convert to fraction form
   9,118.72/12,584.08 = 5,139.96/x
3. Step 3: Cross multiply
   9,118.72x = 12,584.08 × 5,139.96
4. Step 4: Simplify right side
   9,118.72x = 64,681,667.84
5. Step 5: Solve for x
   x = 64,681,667.84/9,118.72
6. Step 6: Final answer
   x = 7,093.28