Finding the Third Proportional to 13,218.50 and 20,499

Step by Step Solution

1. Step 1: Write the proportion equation
   13,218.50 : 20,499 = 20,499 : x
2. Step 2: Convert to fraction form
   13,218.50/20,499 = 20,499/x
3. Step 3: Cross multiply
   13,218.50x = 20,499 × 20,499
4. Step 4: Simplify right side
   13,218.50x = 420,209,001
5. Step 5: Solve for x
   x = 420,209,001/13,218.50
6. Step 6: Final answer
   x = 31,789.46