Finding the Third Proportional to 381,688 and 518,371.50

Step by Step Solution

1. Step 1: Write the proportion equation
   381,688 : 518,371.50 = 518,371.50 : x
2. Step 2: Convert to fraction form
   381,688/518,371.50 = 518,371.50/x
3. Step 3: Cross multiply
   381,688x = 518,371.50 × 518,371.50
4. Step 4: Simplify right side
   381,688x = 268,709,012,012.25
5. Step 5: Solve for x
   x = 268,709,012,012.25/381,688
6. Step 6: Final answer
   x = 704,001.73