Finding the Fourth Proportional to 13,665.59, 20,501.28 and 7,745.31

Step by Step Solution

1. Step 1: Write the proportion equation
   13,665.59 : 20,501.28 = 7,745.31 : x
2. Step 2: Convert to fraction form
   13,665.59/20,501.28 = 7,745.31/x
3. Step 3: Cross multiply
   13,665.59x = 20,501.28 × 7,745.31
4. Step 4: Simplify right side
   13,665.59x = 158,788,769.00
5. Step 5: Solve for x
   x = 158,788,769.00/13,665.59
6. Step 6: Final answer
   x = 11,619.61