Finding the Third Proportional to 9,555 and 12,721.50

Step by Step Solution

1. Step 1: Write the proportion equation
   9,555 : 12,721.50 = 12,721.50 : x
2. Step 2: Convert to fraction form
   9,555/12,721.50 = 12,721.50/x
3. Step 3: Cross multiply
   9,555x = 12,721.50 × 12,721.50
4. Step 4: Simplify right side
   9,555x = 161,836,562.25
5. Step 5: Solve for x
   x = 161,836,562.25/9,555
6. Step 6: Final answer
   x = 16,937.37