Finding the Third Proportional to 315,810 and 485,429

Step by Step Solution

1. Step 1: Write the proportion equation
   315,810 : 485,429 = 485,429 : x
2. Step 2: Convert to fraction form
   315,810/485,429 = 485,429/x
3. Step 3: Cross multiply
   315,810x = 485,429 × 485,429
4. Step 4: Simplify right side
   315,810x = 235,641,314,041
5. Step 5: Solve for x
   x = 235,641,314,041/315,810
6. Step 6: Final answer
   x = 746,148.99