Finding the Third Proportional to 257,988 and 388,494

Step by Step Solution

1. Step 1: Write the proportion equation
   257,988 : 388,494 = 388,494 : x
2. Step 2: Convert to fraction form
   257,988/388,494 = 388,494/x
3. Step 3: Cross multiply
   257,988x = 388,494 × 388,494
4. Step 4: Simplify right side
   257,988x = 150,927,588,036
5. Step 5: Solve for x
   x = 150,927,588,036/257,988
6. Step 6: Final answer
   x = 585,017.86