Finding the Third Proportional to 99,818 and 218,142

Step by Step Solution

1. Step 1: Write the proportion equation
   99,818 : 218,142 = 218,142 : x
2. Step 2: Convert to fraction form
   99,818/218,142 = 218,142/x
3. Step 3: Cross multiply
   99,818x = 218,142 × 218,142
4. Step 4: Simplify right side
   99,818x = 47,585,932,164
5. Step 5: Solve for x
   x = 47,585,932,164/99,818
6. Step 6: Final answer
   x = 476,726.96