Finding the Fourth Proportional to 5,642.58, 8,478.90 and 5,287.89

Step by Step Solution

1. Step 1: Write the proportion equation
   5,642.58 : 8,478.90 = 5,287.89 : x
2. Step 2: Convert to fraction form
   5,642.58/8,478.90 = 5,287.89/x
3. Step 3: Cross multiply
   5,642.58x = 8,478.90 × 5,287.89
4. Step 4: Simplify right side
   5,642.58x = 44,835,490.52
5. Step 5: Solve for x
   x = 44,835,490.52/5,642.58
6. Step 6: Final answer
   x = 7,945.92