Finding the Fourth Proportional to 12,817.86, 17,687.97 and 7,228.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,817.86 : 17,687.97 = 7,228.50 : x
2. Step 2: Convert to fraction form
   12,817.86/17,687.97 = 7,228.50/x
3. Step 3: Cross multiply
   12,817.86x = 17,687.97 × 7,228.50
4. Step 4: Simplify right side
   12,817.86x = 127,857,491.15
5. Step 5: Solve for x
   x = 127,857,491.15/12,817.86
6. Step 6: Final answer
   x = 9,974.95