Finding the Third Proportional to 99,180 and 215,856

Step by Step Solution

1. Step 1: Write the proportion equation
   99,180 : 215,856 = 215,856 : x
2. Step 2: Convert to fraction form
   99,180/215,856 = 215,856/x
3. Step 3: Cross multiply
   99,180x = 215,856 × 215,856
4. Step 4: Simplify right side
   99,180x = 46,593,812,736
5. Step 5: Solve for x
   x = 46,593,812,736/99,180
6. Step 6: Final answer
   x = 469,790.41