Finding the Third Proportional to 9,139 and 19,691

Step by Step Solution

1. Step 1: Write the proportion equation
   9,139 : 19,691 = 19,691 : x
2. Step 2: Convert to fraction form
   9,139/19,691 = 19,691/x
3. Step 3: Cross multiply
   9,139x = 19,691 × 19,691
4. Step 4: Simplify right side
   9,139x = 387,735,481
5. Step 5: Solve for x
   x = 387,735,481/9,139
6. Step 6: Final answer
   x = 42,426.47