Finding the Third Proportional to 291,866.50 and 639,092

Step by Step Solution

1. Step 1: Write the proportion equation
   291,866.50 : 639,092 = 639,092 : x
2. Step 2: Convert to fraction form
   291,866.50/639,092 = 639,092/x
3. Step 3: Cross multiply
   291,866.50x = 639,092 × 639,092
4. Step 4: Simplify right side
   291,866.50x = 408,438,584,464
5. Step 5: Solve for x
   x = 408,438,584,464/291,866.50
6. Step 6: Final answer
   x = 1,399,402.07