Finding the Third Proportional to 354,320 and 538,040

Step by Step Solution

1. Step 1: Write the proportion equation
   354,320 : 538,040 = 538,040 : x
2. Step 2: Convert to fraction form
   354,320/538,040 = 538,040/x
3. Step 3: Cross multiply
   354,320x = 538,040 × 538,040
4. Step 4: Simplify right side
   354,320x = 289,487,041,600
5. Step 5: Solve for x
   x = 289,487,041,600/354,320
6. Step 6: Final answer
   x = 817,021.45