Finding the Third Proportional to 19,643 and 42,399

Step by Step Solution

1. Step 1: Write the proportion equation
   19,643 : 42,399 = 42,399 : x
2. Step 2: Convert to fraction form
   19,643/42,399 = 42,399/x
3. Step 3: Cross multiply
   19,643x = 42,399 × 42,399
4. Step 4: Simplify right side
   19,643x = 1,797,675,201
5. Step 5: Solve for x
   x = 1,797,675,201/19,643
6. Step 6: Final answer
   x = 91,517.34