Finding the Fourth Proportional to 10,128.20, 13,977 and 5,651.90

Step by Step Solution

1. Step 1: Write the proportion equation
   10,128.20 : 13,977 = 5,651.90 : x
2. Step 2: Convert to fraction form
   10,128.20/13,977 = 5,651.90/x
3. Step 3: Cross multiply
   10,128.20x = 13,977 × 5,651.90
4. Step 4: Simplify right side
   10,128.20x = 78,996,606.30
5. Step 5: Solve for x
   x = 78,996,606.30/10,128.20
6. Step 6: Final answer
   x = 7,799.67