Finding the Third Proportional to 102,401 and 212,978

Step by Step Solution

1. Step 1: Write the proportion equation
   102,401 : 212,978 = 212,978 : x
2. Step 2: Convert to fraction form
   102,401/212,978 = 212,978/x
3. Step 3: Cross multiply
   102,401x = 212,978 × 212,978
4. Step 4: Simplify right side
   102,401x = 45,359,628,484
5. Step 5: Solve for x
   x = 45,359,628,484/102,401
6. Step 6: Final answer
   x = 442,960.80