Finding the Third Proportional to 8,640.56 and 13,040.06

Step by Step Solution

1. Step 1: Write the proportion equation
   8,640.56 : 13,040.06 = 13,040.06 : x
2. Step 2: Convert to fraction form
   8,640.56/13,040.06 = 13,040.06/x
3. Step 3: Cross multiply
   8,640.56x = 13,040.06 × 13,040.06
4. Step 4: Simplify right side
   8,640.56x = 170,043,230.00
5. Step 5: Solve for x
   x = 170,043,230.00/8,640.56
6. Step 6: Final answer
   x = 19,679.65