Finding the Fourth Proportional to 12,928.89, 19,392.25 and 5,135.61

Step by Step Solution

1. Step 1: Write the proportion equation
   12,928.89 : 19,392.25 = 5,135.61 : x
2. Step 2: Convert to fraction form
   12,928.89/19,392.25 = 5,135.61/x
3. Step 3: Cross multiply
   12,928.89x = 19,392.25 × 5,135.61
4. Step 4: Simplify right side
   12,928.89x = 99,591,033.02
5. Step 5: Solve for x
   x = 99,591,033.02/12,928.89
6. Step 6: Final answer
   x = 7,702.98