Finding the Fourth Proportional to 12,966.40, 17,890.58 and 7,662.02

Step by Step Solution

1. Step 1: Write the proportion equation
   12,966.40 : 17,890.58 = 7,662.02 : x
2. Step 2: Convert to fraction form
   12,966.40/17,890.58 = 7,662.02/x
3. Step 3: Cross multiply
   12,966.40x = 17,890.58 × 7,662.02
4. Step 4: Simplify right side
   12,966.40x = 137,077,981.77
5. Step 5: Solve for x
   x = 137,077,981.77/12,966.40
6. Step 6: Final answer
   x = 10,571.78