Finding the Third Proportional to 266,688 and 389,499

Step by Step Solution

1. Step 1: Write the proportion equation
   266,688 : 389,499 = 389,499 : x
2. Step 2: Convert to fraction form
   266,688/389,499 = 389,499/x
3. Step 3: Cross multiply
   266,688x = 389,499 × 389,499
4. Step 4: Simplify right side
   266,688x = 151,709,471,001
5. Step 5: Solve for x
   x = 151,709,471,001/266,688
6. Step 6: Final answer
   x = 568,865.01