Finding the Third Proportional to 90,902 and 212,309

Step by Step Solution

1. Step 1: Write the proportion equation
   90,902 : 212,309 = 212,309 : x
2. Step 2: Convert to fraction form
   90,902/212,309 = 212,309/x
3. Step 3: Cross multiply
   90,902x = 212,309 × 212,309
4. Step 4: Simplify right side
   90,902x = 45,075,111,481
5. Step 5: Solve for x
   x = 45,075,111,481/90,902
6. Step 6: Final answer
   x = 495,864.90