Finding the Third Proportional to 99,904 and 213,978

Step by Step Solution

1. Step 1: Write the proportion equation
   99,904 : 213,978 = 213,978 : x
2. Step 2: Convert to fraction form
   99,904/213,978 = 213,978/x
3. Step 3: Cross multiply
   99,904x = 213,978 × 213,978
4. Step 4: Simplify right side
   99,904x = 45,786,584,484
5. Step 5: Solve for x
   x = 45,786,584,484/99,904
6. Step 6: Final answer
   x = 458,305.82