Finding the Third Proportional to 312,635.50 and 636,320

Step by Step Solution

1. Step 1: Write the proportion equation
   312,635.50 : 636,320 = 636,320 : x
2. Step 2: Convert to fraction form
   312,635.50/636,320 = 636,320/x
3. Step 3: Cross multiply
   312,635.50x = 636,320 × 636,320
4. Step 4: Simplify right side
   312,635.50x = 404,903,142,400
5. Step 5: Solve for x
   x = 404,903,142,400/312,635.50
6. Step 6: Final answer
   x = 1,295,128.49