Finding the Fourth Proportional to 5,499.20, 7,720.75 and 5,499.20

Step by Step Solution

1. Step 1: Write the proportion equation
   5,499.20 : 7,720.75 = 5,499.20 : x
2. Step 2: Convert to fraction form
   5,499.20/7,720.75 = 5,499.20/x
3. Step 3: Cross multiply
   5,499.20x = 7,720.75 × 5,499.20
4. Step 4: Simplify right side
   5,499.20x = 42,457,948.40
5. Step 5: Solve for x
   x = 42,457,948.40/5,499.20
6. Step 6: Final answer
   x = 7,720.75