Finding the Third Proportional to 9,940 and 20,520

Step by Step Solution

1. Step 1: Write the proportion equation
   9,940 : 20,520 = 20,520 : x
2. Step 2: Convert to fraction form
   9,940/20,520 = 20,520/x
3. Step 3: Cross multiply
   9,940x = 20,520 × 20,520
4. Step 4: Simplify right side
   9,940x = 421,070,400
5. Step 5: Solve for x
   x = 421,070,400/9,940
6. Step 6: Final answer
   x = 42,361.21