Finding the Third Proportional to 9,990 and 16,650

Step by Step Solution

1. Step 1: Write the proportion equation
   9,990 : 16,650 = 16,650 : x
2. Step 2: Convert to fraction form
   9,990/16,650 = 16,650/x
3. Step 3: Cross multiply
   9,990x = 16,650 × 16,650
4. Step 4: Simplify right side
   9,990x = 277,222,500
5. Step 5: Solve for x
   x = 277,222,500/9,990
6. Step 6: Final answer
   x = 27,750