Finding the Third Proportional to 399,978 and 562,542

Step by Step Solution

1. Step 1: Write the proportion equation
   399,978 : 562,542 = 562,542 : x
2. Step 2: Convert to fraction form
   399,978/562,542 = 562,542/x
3. Step 3: Cross multiply
   399,978x = 562,542 × 562,542
4. Step 4: Simplify right side
   399,978x = 316,453,501,764
5. Step 5: Solve for x
   x = 316,453,501,764/399,978
6. Step 6: Final answer
   x = 791,177.27