Finding the Fourth Proportional to 5,642.27, 8,454.06 and 3,990.63

Step by Step Solution

1. Step 1: Write the proportion equation
   5,642.27 : 8,454.06 = 3,990.63 : x
2. Step 2: Convert to fraction form
   5,642.27/8,454.06 = 3,990.63/x
3. Step 3: Cross multiply
   5,642.27x = 8,454.06 × 3,990.63
4. Step 4: Simplify right side
   5,642.27x = 33,737,025.46
5. Step 5: Solve for x
   x = 33,737,025.46/5,642.27
6. Step 6: Final answer
   x = 5,979.34