Finding the Third Proportional to 311,953.50 and 638,655

Step by Step Solution

1. Step 1: Write the proportion equation
   311,953.50 : 638,655 = 638,655 : x
2. Step 2: Convert to fraction form
   311,953.50/638,655 = 638,655/x
3. Step 3: Cross multiply
   311,953.50x = 638,655 × 638,655
4. Step 4: Simplify right side
   311,953.50x = 407,880,209,025
5. Step 5: Solve for x
   x = 407,880,209,025/311,953.50
6. Step 6: Final answer
   x = 1,307,503.23