Finding the Fourth Proportional to 5,563.28, 7,687.56 and 3,988.88

Step by Step Solution

1. Step 1: Write the proportion equation
   5,563.28 : 7,687.56 = 3,988.88 : x
2. Step 2: Convert to fraction form
   5,563.28/7,687.56 = 3,988.88/x
3. Step 3: Cross multiply
   5,563.28x = 7,687.56 × 3,988.88
4. Step 4: Simplify right side
   5,563.28x = 30,664,754.33
5. Step 5: Solve for x
   x = 30,664,754.33/5,563.28
6. Step 6: Final answer
   x = 5,511.99