Finding the Third Proportional to 311,557.50 and 677,790

Step by Step Solution

1. Step 1: Write the proportion equation
   311,557.50 : 677,790 = 677,790 : x
2. Step 2: Convert to fraction form
   311,557.50/677,790 = 677,790/x
3. Step 3: Cross multiply
   311,557.50x = 677,790 × 677,790
4. Step 4: Simplify right side
   311,557.50x = 459,399,284,100
5. Step 5: Solve for x
   x = 459,399,284,100/311,557.50
6. Step 6: Final answer
   x = 1,474,524.88