Finding the Third Proportional to 209,172 and 320,040

Step by Step Solution

1. Step 1: Write the proportion equation
   209,172 : 320,040 = 320,040 : x
2. Step 2: Convert to fraction form
   209,172/320,040 = 320,040/x
3. Step 3: Cross multiply
   209,172x = 320,040 × 320,040
4. Step 4: Simplify right side
   209,172x = 102,425,601,600
5. Step 5: Solve for x
   x = 102,425,601,600/209,172
6. Step 6: Final answer
   x = 489,671.67