Finding the Third Proportional to 287,969.50 and 387,664

Step by Step Solution

1. Step 1: Write the proportion equation
   287,969.50 : 387,664 = 387,664 : x
2. Step 2: Convert to fraction form
   287,969.50/387,664 = 387,664/x
3. Step 3: Cross multiply
   287,969.50x = 387,664 × 387,664
4. Step 4: Simplify right side
   287,969.50x = 150,283,376,896
5. Step 5: Solve for x
   x = 150,283,376,896/287,969.50
6. Step 6: Final answer
   x = 521,872.55