Finding the Third Proportional to 201,123 and 320,137.50

Step by Step Solution

1. Step 1: Write the proportion equation
   201,123 : 320,137.50 = 320,137.50 : x
2. Step 2: Convert to fraction form
   201,123/320,137.50 = 320,137.50/x
3. Step 3: Cross multiply
   201,123x = 320,137.50 × 320,137.50
4. Step 4: Simplify right side
   201,123x = 102,488,018,906.25
5. Step 5: Solve for x
   x = 102,488,018,906.25/201,123
6. Step 6: Final answer
   x = 509,578.81