Finding the Fourth Proportional to 5,139.56, 7,712.43 and 2,217.86

Step by Step Solution

1. Step 1: Write the proportion equation
   5,139.56 : 7,712.43 = 2,217.86 : x
2. Step 2: Convert to fraction form
   5,139.56/7,712.43 = 2,217.86/x
3. Step 3: Cross multiply
   5,139.56x = 7,712.43 × 2,217.86
4. Step 4: Simplify right side
   5,139.56x = 17,105,103.74
5. Step 5: Solve for x
   x = 17,105,103.74/5,139.56
6. Step 6: Final answer
   x = 3,328.13