Finding the Third Proportional to 299,651.50 and 643,772

Step by Step Solution

1. Step 1: Write the proportion equation
   299,651.50 : 643,772 = 643,772 : x
2. Step 2: Convert to fraction form
   299,651.50/643,772 = 643,772/x
3. Step 3: Cross multiply
   299,651.50x = 643,772 × 643,772
4. Step 4: Simplify right side
   299,651.50x = 414,442,387,984
5. Step 5: Solve for x
   x = 414,442,387,984/299,651.50
6. Step 6: Final answer
   x = 1,383,081.31