Finding the Third Proportional to 99,920 and 216,670

Step by Step Solution

1. Step 1: Write the proportion equation
   99,920 : 216,670 = 216,670 : x
2. Step 2: Convert to fraction form
   99,920/216,670 = 216,670/x
3. Step 3: Cross multiply
   99,920x = 216,670 × 216,670
4. Step 4: Simplify right side
   99,920x = 46,945,888,900
5. Step 5: Solve for x
   x = 46,945,888,900/99,920
6. Step 6: Final answer
   x = 469,834.76