Finding the Fourth Proportional to 5,128.71, 7,693.28 and 2,661.94

Step by Step Solution

1. Step 1: Write the proportion equation
   5,128.71 : 7,693.28 = 2,661.94 : x
2. Step 2: Convert to fraction form
   5,128.71/7,693.28 = 2,661.94/x
3. Step 3: Cross multiply
   5,128.71x = 7,693.28 × 2,661.94
4. Step 4: Simplify right side
   5,128.71x = 20,479,049.76
5. Step 5: Solve for x
   x = 20,479,049.76/5,128.71
6. Step 6: Final answer
   x = 3,993.02