Finding the Third Proportional to 315,339.75 and 689,364

Step by Step Solution

1. Step 1: Write the proportion equation
   315,339.75 : 689,364 = 689,364 : x
2. Step 2: Convert to fraction form
   315,339.75/689,364 = 689,364/x
3. Step 3: Cross multiply
   315,339.75x = 689,364 × 689,364
4. Step 4: Simplify right side
   315,339.75x = 475,222,724,496
5. Step 5: Solve for x
   x = 475,222,724,496/315,339.75
6. Step 6: Final answer
   x = 1,507,018.14