Finding the Fourth Proportional to 12,456.10, 17,188.77 and 7,740.28

Step by Step Solution

1. Step 1: Write the proportion equation
   12,456.10 : 17,188.77 = 7,740.28 : x
2. Step 2: Convert to fraction form
   12,456.10/17,188.77 = 7,740.28/x
3. Step 3: Cross multiply
   12,456.10x = 17,188.77 × 7,740.28
4. Step 4: Simplify right side
   12,456.10x = 133,045,892.66
5. Step 5: Solve for x
   x = 133,045,892.66/12,456.10
6. Step 6: Final answer
   x = 10,681.18