Finding the Third Proportional to 13,142 and 20,406

Step by Step Solution

1. Step 1: Write the proportion equation
   13,142 : 20,406 = 20,406 : x
2. Step 2: Convert to fraction form
   13,142/20,406 = 20,406/x
3. Step 3: Cross multiply
   13,142x = 20,406 × 20,406
4. Step 4: Simplify right side
   13,142x = 416,404,836
5. Step 5: Solve for x
   x = 416,404,836/13,142
6. Step 6: Final answer
   x = 31,685.04