Finding the Third Proportional to 19,664 and 42,109

Step by Step Solution

1. Step 1: Write the proportion equation
   19,664 : 42,109 = 42,109 : x
2. Step 2: Convert to fraction form
   19,664/42,109 = 42,109/x
3. Step 3: Cross multiply
   19,664x = 42,109 × 42,109
4. Step 4: Simplify right side
   19,664x = 1,773,167,881
5. Step 5: Solve for x
   x = 1,773,167,881/19,664
6. Step 6: Final answer
   x = 90,173.31