Finding the Fourth Proportional to 12,456.86, 17,188.65 and 7,151.90

Step by Step Solution

1. Step 1: Write the proportion equation
   12,456.86 : 17,188.65 = 7,151.90 : x
2. Step 2: Convert to fraction form
   12,456.86/17,188.65 = 7,151.90/x
3. Step 3: Cross multiply
   12,456.86x = 17,188.65 × 7,151.90
4. Step 4: Simplify right side
   12,456.86x = 122,931,505.94
5. Step 5: Solve for x
   x = 122,931,505.94/12,456.86
6. Step 6: Final answer
   x = 9,868.58