Finding the Third Proportional to 311,610 and 688,612.50

Step by Step Solution

1. Step 1: Write the proportion equation
   311,610 : 688,612.50 = 688,612.50 : x
2. Step 2: Convert to fraction form
   311,610/688,612.50 = 688,612.50/x
3. Step 3: Cross multiply
   311,610x = 688,612.50 × 688,612.50
4. Step 4: Simplify right side
   311,610x = 474,187,175,156.25
5. Step 5: Solve for x
   x = 474,187,175,156.25/311,610
6. Step 6: Final answer
   x = 1,521,732.86