Finding the Fourth Proportional to 10,139.11, 13,972.04 and 7,751.78

Step by Step Solution

1. Step 1: Write the proportion equation
   10,139.11 : 13,972.04 = 7,751.78 : x
2. Step 2: Convert to fraction form
   10,139.11/13,972.04 = 7,751.78/x
3. Step 3: Cross multiply
   10,139.11x = 13,972.04 × 7,751.78
4. Step 4: Simplify right side
   10,139.11x = 108,308,141.47
5. Step 5: Solve for x
   x = 108,308,141.47/10,139.11
6. Step 6: Final answer
   x = 10,682.21