Finding the Third Proportional to 13,218.94 and 20,478.38

Step by Step Solution

1. Step 1: Write the proportion equation
   13,218.94 : 20,478.38 = 20,478.38 : x
2. Step 2: Convert to fraction form
   13,218.94/20,478.38 = 20,478.38/x
3. Step 3: Cross multiply
   13,218.94x = 20,478.38 × 20,478.38
4. Step 4: Simplify right side
   13,218.94x = 419,363,842.64
5. Step 5: Solve for x
   x = 419,363,842.64/13,218.94
6. Step 6: Final answer
   x = 31,724.47