Finding the Third Proportional to 9,911 and 21,665

Step by Step Solution

1. Step 1: Write the proportion equation
   9,911 : 21,665 = 21,665 : x
2. Step 2: Convert to fraction form
   9,911/21,665 = 21,665/x
3. Step 3: Cross multiply
   9,911x = 21,665 × 21,665
4. Step 4: Simplify right side
   9,911x = 469,372,225
5. Step 5: Solve for x
   x = 469,372,225/9,911
6. Step 6: Final answer
   x = 47,358.72