Finding the Third Proportional to 421,443 and 667,156.50

Step by Step Solution

1. Step 1: Write the proportion equation
   421,443 : 667,156.50 = 667,156.50 : x
2. Step 2: Convert to fraction form
   421,443/667,156.50 = 667,156.50/x
3. Step 3: Cross multiply
   421,443x = 667,156.50 × 667,156.50
4. Step 4: Simplify right side
   421,443x = 445,097,795,492.25
5. Step 5: Solve for x
   x = 445,097,795,492.25/421,443
6. Step 6: Final answer
   x = 1,056,128.10