Finding the Third Proportional to 291,849 and 639,055.50

Step by Step Solution

1. Step 1: Write the proportion equation
   291,849 : 639,055.50 = 639,055.50 : x
2. Step 2: Convert to fraction form
   291,849/639,055.50 = 639,055.50/x
3. Step 3: Cross multiply
   291,849x = 639,055.50 × 639,055.50
4. Step 4: Simplify right side
   291,849x = 408,391,932,080.25
5. Step 5: Solve for x
   x = 408,391,932,080.25/291,849
6. Step 6: Final answer
   x = 1,399,326.13