Finding the Third Proportional to 316,609.50 and 666,019.50

Step by Step Solution

1. Step 1: Write the proportion equation
   316,609.50 : 666,019.50 = 666,019.50 : x
2. Step 2: Convert to fraction form
   316,609.50/666,019.50 = 666,019.50/x
3. Step 3: Cross multiply
   316,609.50x = 666,019.50 × 666,019.50
4. Step 4: Simplify right side
   316,609.50x = 443,581,974,380.25
5. Step 5: Solve for x
   x = 443,581,974,380.25/316,609.50
6. Step 6: Final answer
   x = 1,401,038.11