Finding the Third Proportional to 123,990 and 268,580

Step by Step Solution

1. Step 1: Write the proportion equation
   123,990 : 268,580 = 268,580 : x
2. Step 2: Convert to fraction form
   123,990/268,580 = 268,580/x
3. Step 3: Cross multiply
   123,990x = 268,580 × 268,580
4. Step 4: Simplify right side
   123,990x = 72,135,216,400
5. Step 5: Solve for x
   x = 72,135,216,400/123,990
6. Step 6: Final answer
   x = 581,782.53