Finding the Third Proportional to 217,942 and 300,128

Step by Step Solution

1. Step 1: Write the proportion equation
   217,942 : 300,128 = 300,128 : x
2. Step 2: Convert to fraction form
   217,942/300,128 = 300,128/x
3. Step 3: Cross multiply
   217,942x = 300,128 × 300,128
4. Step 4: Simplify right side
   217,942x = 90,076,816,384
5. Step 5: Solve for x
   x = 90,076,816,384/217,942
6. Step 6: Final answer
   x = 413,306.37