Finding the Third Proportional to 19,640 and 42,419

Step by Step Solution

1. Step 1: Write the proportion equation
   19,640 : 42,419 = 42,419 : x
2. Step 2: Convert to fraction form
   19,640/42,419 = 42,419/x
3. Step 3: Cross multiply
   19,640x = 42,419 × 42,419
4. Step 4: Simplify right side
   19,640x = 1,799,371,561
5. Step 5: Solve for x
   x = 1,799,371,561/19,640
6. Step 6: Final answer
   x = 91,617.70