Finding the Fourth Proportional to 9,139.28, 12,612.15 and 4,947.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,139.28 : 12,612.15 = 4,947.50 : x
2. Step 2: Convert to fraction form
   9,139.28/12,612.15 = 4,947.50/x
3. Step 3: Cross multiply
   9,139.28x = 12,612.15 × 4,947.50
4. Step 4: Simplify right side
   9,139.28x = 62,398,612.13
5. Step 5: Solve for x
   x = 62,398,612.13/9,139.28
6. Step 6: Final answer
   x = 6,827.52