Finding the Third Proportional to 20,388 and 42,087

Step by Step Solution

1. Step 1: Write the proportion equation
   20,388 : 42,087 = 42,087 : x
2. Step 2: Convert to fraction form
   20,388/42,087 = 42,087/x
3. Step 3: Cross multiply
   20,388x = 42,087 × 42,087
4. Step 4: Simplify right side
   20,388x = 1,771,315,569
5. Step 5: Solve for x
   x = 1,771,315,569/20,388
6. Step 6: Final answer
   x = 86,880.30