Finding the Third Proportional to 301,830 and 639,640.50

Step by Step Solution

1. Step 1: Write the proportion equation
   301,830 : 639,640.50 = 639,640.50 : x
2. Step 2: Convert to fraction form
   301,830/639,640.50 = 639,640.50/x
3. Step 3: Cross multiply
   301,830x = 639,640.50 × 639,640.50
4. Step 4: Simplify right side
   301,830x = 409,139,969,240.25
5. Step 5: Solve for x
   x = 409,139,969,240.25/301,830
6. Step 6: Final answer
   x = 1,355,531.16