Finding the Fourth Proportional to 10,129.20, 13,978.89 and 5,653.14

Step by Step Solution

1. Step 1: Write the proportion equation
   10,129.20 : 13,978.89 = 5,653.14 : x
2. Step 2: Convert to fraction form
   10,129.20/13,978.89 = 5,653.14/x
3. Step 3: Cross multiply
   10,129.20x = 13,978.89 × 5,653.14
4. Step 4: Simplify right side
   10,129.20x = 79,024,622.21
5. Step 5: Solve for x
   x = 79,024,622.21/10,129.20
6. Step 6: Final answer
   x = 7,801.66