Finding the Fourth Proportional to 2,939.47, 4,385.69 and 2,800.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,939.47 : 4,385.69 = 2,800.15 : x
2. Step 2: Convert to fraction form
   2,939.47/4,385.69 = 2,800.15/x
3. Step 3: Cross multiply
   2,939.47x = 4,385.69 × 2,800.15
4. Step 4: Simplify right side
   2,939.47x = 12,280,589.85
5. Step 5: Solve for x
   x = 12,280,589.85/2,939.47
6. Step 6: Final answer
   x = 4,177.82