Finding the Third Proportional to 9,930 and 21,315

Step by Step Solution

1. Step 1: Write the proportion equation
   9,930 : 21,315 = 21,315 : x
2. Step 2: Convert to fraction form
   9,930/21,315 = 21,315/x
3. Step 3: Cross multiply
   9,930x = 21,315 × 21,315
4. Step 4: Simplify right side
   9,930x = 454,329,225
5. Step 5: Solve for x
   x = 454,329,225/9,930
6. Step 6: Final answer
   x = 45,753.19