Finding the Third Proportional to 99,090 and 213,972

Step by Step Solution

1. Step 1: Write the proportion equation
   99,090 : 213,972 = 213,972 : x
2. Step 2: Convert to fraction form
   99,090/213,972 = 213,972/x
3. Step 3: Cross multiply
   99,090x = 213,972 × 213,972
4. Step 4: Simplify right side
   99,090x = 45,784,016,784
5. Step 5: Solve for x
   x = 45,784,016,784/99,090
6. Step 6: Final answer
   x = 462,044.78