Finding the Third Proportional to 356,904 and 538,380

Step by Step Solution

1. Step 1: Write the proportion equation
   356,904 : 538,380 = 538,380 : x
2. Step 2: Convert to fraction form
   356,904/538,380 = 538,380/x
3. Step 3: Cross multiply
   356,904x = 538,380 × 538,380
4. Step 4: Simplify right side
   356,904x = 289,853,024,400
5. Step 5: Solve for x
   x = 289,853,024,400/356,904
6. Step 6: Final answer
   x = 812,131.62