Finding the Third Proportional to 315,447.75 and 684,139.50

Step by Step Solution

1. Step 1: Write the proportion equation
   315,447.75 : 684,139.50 = 684,139.50 : x
2. Step 2: Convert to fraction form
   315,447.75/684,139.50 = 684,139.50/x
3. Step 3: Cross multiply
   315,447.75x = 684,139.50 × 684,139.50
4. Step 4: Simplify right side
   315,447.75x = 468,046,855,460.25
5. Step 5: Solve for x
   x = 468,046,855,460.25/315,447.75
6. Step 6: Final answer
   x = 1,483,753.98