Finding the Fourth Proportional to 12,721.12, 17,555.26 and 7,055.55

Step by Step Solution

1. Step 1: Write the proportion equation
   12,721.12 : 17,555.26 = 7,055.55 : x
2. Step 2: Convert to fraction form
   12,721.12/17,555.26 = 7,055.55/x
3. Step 3: Cross multiply
   12,721.12x = 17,555.26 × 7,055.55
4. Step 4: Simplify right side
   12,721.12x = 123,862,014.69
5. Step 5: Solve for x
   x = 123,862,014.69/12,721.12
6. Step 6: Final answer
   x = 9,736.72