Finding the Fourth Proportional to 10,686.84, 16,026.16 and 5,138.88

Step by Step Solution

1. Step 1: Write the proportion equation
   10,686.84 : 16,026.16 = 5,138.88 : x
2. Step 2: Convert to fraction form
   10,686.84/16,026.16 = 5,138.88/x
3. Step 3: Cross multiply
   10,686.84x = 16,026.16 × 5,138.88
4. Step 4: Simplify right side
   10,686.84x = 82,356,513.10
5. Step 5: Solve for x
   x = 82,356,513.10/10,686.84
6. Step 6: Final answer
   x = 7,706.35