Finding the Third Proportional to 123,978 and 254,490

Step by Step Solution

1. Step 1: Write the proportion equation
   123,978 : 254,490 = 254,490 : x
2. Step 2: Convert to fraction form
   123,978/254,490 = 254,490/x
3. Step 3: Cross multiply
   123,978x = 254,490 × 254,490
4. Step 4: Simplify right side
   123,978x = 64,765,160,100
5. Step 5: Solve for x
   x = 64,765,160,100/123,978
6. Step 6: Final answer
   x = 522,392.36