Finding the Fourth Proportional to 10,689.97, 16,038.42 and 5,142.59

Step by Step Solution

1. Step 1: Write the proportion equation
   10,689.97 : 16,038.42 = 5,142.59 : x
2. Step 2: Convert to fraction form
   10,689.97/16,038.42 = 5,142.59/x
3. Step 3: Cross multiply
   10,689.97x = 16,038.42 × 5,142.59
4. Step 4: Simplify right side
   10,689.97x = 82,479,018.31
5. Step 5: Solve for x
   x = 82,479,018.31/10,689.97
6. Step 6: Final answer
   x = 7,715.55