Finding the Fourth Proportional to 12,992.48, 17,934.40 and 7,689.12

Step by Step Solution

1. Step 1: Write the proportion equation
   12,992.48 : 17,934.40 = 7,689.12 : x
2. Step 2: Convert to fraction form
   12,992.48/17,934.40 = 7,689.12/x
3. Step 3: Cross multiply
   12,992.48x = 17,934.40 × 7,689.12
4. Step 4: Simplify right side
   12,992.48x = 137,899,753.73
5. Step 5: Solve for x
   x = 137,899,753.73/12,992.48
6. Step 6: Final answer
   x = 10,613.81