Finding the Fourth Proportional to 12,505.77, 17,257.29 and 7,128.18

Step by Step Solution

1. Step 1: Write the proportion equation
   12,505.77 : 17,257.29 = 7,128.18 : x
2. Step 2: Convert to fraction form
   12,505.77/17,257.29 = 7,128.18/x
3. Step 3: Cross multiply
   12,505.77x = 17,257.29 × 7,128.18
4. Step 4: Simplify right side
   12,505.77x = 123,013,069.43
5. Step 5: Solve for x
   x = 123,013,069.43/12,505.77
6. Step 6: Final answer
   x = 9,836.51